Yamamoto Shokai

What Yamamoto Shokai does

Yamamoto Shokai is a Kawasaki-headquartered construction materials trading company founded in 1929, operating as a "total supplier" that aggregates more than 100,000 SKUs from 150+ manufacturers and delivers them directly to construction sites. Its asset base is unusually dense for its category: four branches, more than nineteen sales offices concentrated in the Kanto region, and a fleet of 163 company-owned vehicles enable rapid, site-direct fulfillment. The firm employs approximately 268 people as of October 2025 and operates with ¥495 million in stated capital.

The company's customer base is anchored to Japan's largest general contractors — Obayashi, Kajima, Shimizu, and Takenaka — alongside government and public-sector projects. Its go-to-market is a relationship-driven, phone-and-counter B2B distribution model augmented by site delivery; pricing is transaction-based on materials procurement rather than subscription. The firm has begun modernizing this model, deploying a new core IT system in October 2025 and rebranding its construction-site procurement channel as "CON Mart" in November 2025.

Revenue is generated through trading margins on materials, supplemented by an in-house ecosystem of subsidiaries covering logistics (Yamansho Just), retail (Ticl), vehicle leasing (Iglac), and welfare services (Ishiwatari-no-Higashinokka). Yamamoto Shokai remains privately held under family ownership, with no public revenue disclosure. The combination of a 96-year operating history, blue-chip contractor relationships, and heavy physical distribution assets underpins a stable but customer-concentrated business profile.

Name

Yamamoto Shokai

Legal name

山本商会株式会社

Website

https://y-g.jp

Company type

Private

Founded year

1929

Operating status

Operating

Headcount range

251–500 employees

Short description

Yamamoto Shokai is a Kawasaki-based, family-owned construction materials trading company founded in 1929, supplying 100,000+ SKUs from 150+ manufacturers to Japan's largest general contractors and government agencies across the Kanto region via a dense branch, sales office, and 163-vehicle delivery network.

Ownership category

akta.pro rank

Product category

Construction Materials Distribution

NAICS

Plate Work and Fabricated Structural Product Manufacturing (33231)

SIC

Wholesale-Construction & Mining (No Petro) Machinery & Equip (5082), Sheet Metal Work (3444)

akta.pro primary industry

Steel Products Trading & Service Centers (Flat, Long, Pipe & Tube, Rebar) (IMAKAJAB)

akta.pro secondary industry

Sheet Metal & Ductwork Contracting (IMAFALAH)

Keywords

• Construction materials trading
• Building supplies distribution
• Construction hardware supply
• Civil engineering materials
• Construction site delivery

Headquarters

HQ city

Kawasaki

HQ country

Japan

HQ region

Asia

Offices20 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Personnel, Operations, Infrastructure, Marketing or Sales, Technology or R&D

Revenue model

1. Construction Materials Distribution (Trading): Revenue is generated through the sale of construction materials (steel products, hardware, safety equipment, tools, building materials, etc.) to general contractors, civil engineering companies, and government clients. The company acts as a total supplier (totalサプライヤー), maintaining extensive inventory and distributing products from over 150 manufacturer partners to construction sites. Revenue is transaction-based, driven by order volume from established customers.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels6 records

Core offering

Yamamoto Shokai is a B2B construction materials trading company that acts as a "total supplier" for the construction industry, distributing over 100,000 product SKUs from more than 150 manufacturer partners. The company supplies steel materials, hardware, safety equipment, tools, lumber, electrical materials, and prefabricated metalwork to major general contractors, civil engineering firms, and government agencies. In addition to materials supply, the company provides construction work services spanning metalwork, steel structures, interior finishing, scaffolding, and various specialty trades.

Product overview

Yamamoto Shokai is a construction materials trading company (建設資器の専門商社) that operates as a total supplier for the construction industry. The company offers over 100,000 products from more than 150 manufacturers, organized into 20 major product categories including steel materials, bolts and nuts, safety equipment, tools, electrical materials, lumber, and prefabricated metalwork. The product portfolio is structured around core construction material categories (steel products, hardware, safety equipment, tools) supported by specialized categories (surveying equipment, power tools, cleaning supplies). In addition to physical products, the company operates a proprietary e-commerce platform (originally YG Mart, rebranded as CON Mart in 2025) for online ordering. The company also provides construction work services encompassing metalwork, steel structures, interior work, and various finishing trades. Yamamoto Shokai positions itself between material manufacturers (仕入先企業) and construction companies (得意先企業), providing rapid and stable supply of construction materials to building sites.

Differentiator

Problem solved

Functional benefit

Brands

• YGマート: 自社ECサイト（2021年4月開設、2025年11月にCONマートへ改名）
• CONマート

Products and services

• Construction Materials Supply (Total Supplier Service) Comprehensive supply of over 100,000 construction material SKUs from 150+ manufacturers, spanning steel products, bolts, safety equipment, tools, lumber, electrical materials, and prefabricated metalwork. Designed for general contractors, civil engineering companies, and government agencies requiring rapid delivery of diverse materials to construction sites across the Kanto region.
• Construction Work Services Construction subcontracting services covering finishing work, metalwork, steel structure work, interior work, sheet metal work, scaffolding and earthwork, tile/brick/block work, rebar work, plastering work, roofing work, waterproofing work, thermal insulation work, door work, and fire protection facility work. Available to construction companies and project owners.
• CON Mart (CONマート) E-commerce Platform Proprietary e-commerce platform for online ordering and purchasing of construction materials by existing enterprise customers. Enables self-service digital ordering complementing the company's route sales model.

Quantifiable outcome

• Delivered materials to over 100 landmark construction projects including Tokyo Skytree, National Stadium, K-Arena Yokohama, Haneda Airside Garden, Shibuya Scramble Square, and KADOKAWA Sakura Town

Named customers7 records

Segments3 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature1 record

Partnerships

Five partnerships are on record, tiered minor and core.

• Kawasaki Brave Thunders (川崎ブレイブサンダース)minorGTM or Marketing Partner · 1 March 2024Yamamoto Shokai entered an official sponsor contract with the B.LEAGUE B1 professional basketball club Kawasaki Brave Thunders in March 2024. In August 2025, the company upgraded its sponsorship to include uniform (jersey) sponsorship for the 2025-26 season, displaying its brand on team uniforms. The team is based in Kawasaki City, aligning with Yamamoto Shokai's home territory.
• 山商ジャスト株式会社 (Yamansho Just Co., Ltd.)coreStrategic or Co-development PartnerA consolidated subsidiary handling freight, delivery, and warehouse management operations. Operates under Kanagawa Transportation Bureau permit for general freight trucking in the Tokyo metropolitan area (関自貨2第396号). Capital: ¥90,000,000. This subsidiary is the core logistics and delivery partner supporting Yamamoto Shokai's rapid supply capabilities.
• 株式会社ティクル (Ticl Co., Ltd.)coreStrategic or Co-development PartnerA consolidated subsidiary operating Pro Shop Tickle Kawasaki main branch (proshop・ティクル川崎本店). Handles work clothing, tools sales, and retail store operations. Capital: ¥10,000,000. Provides work apparel and tool retail services potentially serving the same customer base.
• 社会福祉法人 石渡ノ東新家会 (Ishiwatari-no-Higashinokka Social Welfare Corporation)minorOthersOperates Daiishi-ekimae HiyoKo Nursery (大師駅前ひよこ保育園), an approved daycare facility. Supports employee work-life balance by providing childcare services near the headquarters. Capital: ¥500,000.
• 有限公司イグラック (Iglac Co., Ltd.)coreOthersA consolidated subsidiary providing vehicle leasing and office equipment rental services. Capital: ¥500,000. Supports the company's fleet operations and office equipment needs.

Scale indicators6 records

Recent moves9 records

Expansion highlights4 records

Regional players

• Arakawa Shokai Co., Ltd. Construction materials trading company headquartered in Shizuoka, serving the Chubu region of Japan. Operates a comparable product distribution model to Yamamoto Shokai but in a different geographic territory, illustrating a regional peer that has not expanded to Kanto.
• Kanaden Corporation: Listed Japanese trading company distributing electrical, control, and construction-related equipment to industrial and construction customers. Comparable trading-company model serving the contractor segment, though with stronger focus on electrical/control products.

Broad incumbents

• Misumi Group Inc. Major Japanese B2B industrial components distributor with a strong e-commerce catalog model. Competes for indirect procurement spend at manufacturers and contractors; broader portfolio but overlaps with Yamamoto Shokai on factory/MRO consumables.
• Trusco Nakayama Corporation: Large listed Japanese MRO and professional tools distributor with a multi-hundred-thousand SKU catalog and nationwide logistics network. Significantly larger and broader in scope than Yamamoto Shokai, but competes for the same contractor customers and overlap in tools, safety equipment, and consumables categories.
• Yuasa Trading Co., Ltd. Long-established Japanese trading company distributing machinery, industrial equipment, and construction-related products. Broader portfolio than Yamamoto Shokai but overlaps in construction materials and contractor customer segments.

Emerging players

• MonotaRO Co., Ltd. Fast-growing Japanese online MRO and industrial supplies e-commerce platform. Direct competitor to Yamamoto Shokai's CON Mart e-commerce channel for self-service ordering; addresses the same contractor procurement workflow digitally and threatens the route-sales model.

Direct peers

• Furusato Industries Corporation: Listed Japanese trading company distributing construction materials, industrial equipment, and tools to contractors and factories. Operates a regional branch network and product catalog comparable to Yamamoto Shokai's construction materials trading business model.
• Kondotec Inc. Listed Japanese manufacturer and distributor of steel products, structural components, and construction hardware. Overlaps directly with Yamamoto Shokai's steel products trading category and serves similar construction-industry customers via direct sales.
• Naigai Tech Corporation: Listed Japanese industrial materials trading company specializing in safety/protective equipment, tools, and construction consumables. Highly comparable product mix and customer base to Yamamoto Shokai, though with national rather than regional geographic focus.
• Sugimoto Shoji Co., Ltd. Listed Japanese trading company specializing in construction materials, hardware, and steel products, serving general contractors and industrial customers. Operates a comparable total-supplier model with multi-branch distribution and a similar product breadth, making it the closest direct competitor in construction materials trading.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xtwitter.com/YamamotoShokai
• Instagraminstagram.com/yamamotoshokai

Revenue estimate

Valuation estimate

Number of profiles

Profiles12 records

Subsidiaries4 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Yamamoto Shokai