Komatsu Seiki Kosakusho

Company Profile

Message from the President

We started in 1953 with a small town factory that undertakes the assembly of watches. As a cooperating factory of the world watch "SEIKO", we have inherited production + technology and have grown into a company responsible for parts production, mold manufacturing, and stamping. With the proficiency of the watch industry and the transfer to overseas, our business has decided to steer from watches to de-clocking and to develop fine stamping technology for information equipment parts. Since then, the business of information equipment has shrunk due to the overseas production of customers, and due to repeated dangers, the business has been converted to the automobile industry.
Today, the automobile industry is said to be in an era of major transformation of once every 100 years, and our business is also under pressure for further business transformation. However, our microfabrication technology has high expectations in various industries.
We have overcome the crises we have faced many times with our high technology, advanced management, and the human power to support them. We aim to be a company that is useful to the local community and the world with the technology and diverse human resources that have been passed down for 70 years.

President and CEO  Shigeru Komatsu

Company Profile

Company Name Komatsuseiki Kosakusho Co., Ltd.
Established June 1st, 1953
Location 942-2 Shiga Suwa-City, Nagano Prefecture JAPAN
Capital 97.5 Million Yen
Representative President and CEO Shigeru Komatsu
Number of Employees 290 (204 males and 86 females)
Amount of Sales 6.94 billion yen (FY2021)
Fiscal Year From April 1st to March 31st of the Following Year
Business Content Integrated manufacturing of precision stamped parts
Manufacture of various precision machine parts
Automobile parts, Wristwatch parts, Medical Equipment parts, Information Technology Equipment parts, Aerospace parts, Various Mold parts, Jigs and Tools.
Cutting and grinding of difficult-to-cut materials
Major Trading Bank Sumitomo Mitsui Banking Corporation Suwa Branch
Domestic / Overseas Locations Komatsu Seiki (Thailand) Co., Ltd.(Thailand)
Rosies Base Holdings(Boston, MA USA)
nano grains Co., Ltd.
Main Customers Denso Corporation, Robert Bosch GmbH Group, BorgWarner Inc., Aisan Industry Co., Ltd., Nippon Injector Corporation, Hitachi Astemo Co., Ltd.
Seiko-Epson Corporation, etc.

Company History

1953 Established Komatsuseiki Kosakusho LLC as a specialized cooperation company of Seiko Epson Corporation (Founder: Isamu Komatsu) in Kamisuwa, Suwa City.
Capital 200,000 yen (wristwatch parts assembly)
1966 Headquarters factory relocation (current location)
Assembling watch parts → Secondary processing → Surface treatment / heat treatment → Expanding the manufacturing area to stamping
1973 Started in-house Tool Designing and manufacturing stampin tools and built an integrated manufacturing system for parts
1980 Reorganized into Komatsuseiki Kosakusho Co., Ltd.
Increased capital to 67.5 million yen
Takeshi Komatsu inaugurated as President
Isamu Komatsu inaugurated as Chairman of the Board
1981 Entered the IT / Information Equipment Parts Industry
1984 Established Ichinomiya Kogyo LLC. (Shiga Iijima, Suwa City)
Metal processing and sales of bearings, etc.
1985 Entered the Automotive Parts Industry
1997 ISO9002: 1994 certification acquisition
Changed from Ichinomiya Kogyo to KSS Technos Co., Ltd. (Tokyo)
Sales of Tooling parts, sales of precision machine parts
1999 Completion of Building No. 5 (Stamped Parts Factory)
2000 QS-9000: 1998 certification acquisition
2001 ISO14001: 1996 certification acquisition
2002 Established Komatsuseiki (Thailand) Co., Ltd.
(hereinafter referred to as KSTh)
2003 ISO9001: 2000 certification acquisition
2004 ISO/TS16949: 2002 certification acquisition
2005 ISO14001: 2004 certification acquisition
2006 Completion of Building No. 6, Building No. 7 (Cutting parts factory), Building No. 8 (Tool & Die Factory)
2010 ISO9001: 2000 certification acquisition
ISO/TS16949: 2009 certification acquisition
2011 Established KSTh Second Factory
Makoto Komatsu inaugurated as President
Takeshi Komatsu inaugurated as Chairman of the Board
Michio Komatsu becomes Vice Chairman of the Board
2013 Established nano grains Co., Ltd. (ISO13485) as a subsidiary (changed from KSS Technos Co., Ltd.)
2014 Established KSTh Third Factory
2017 Shigeru Komatsu inaugurated as President
Makoto Komatsu inaugurated as Chairman of the Board
Takeshi Komatsu appointed as a consultant
Building No. 10 (cutting parts factory) completed
ISO14001: 2015 certification acquisition
2018 Certified as a “The Driving Company for the regional future” by the Kanto Bureau of Economy, Trade and Industry.
ISO9001: 2015 certification acquisition
IATF16949: 2016 certification acquisition
2019 Registered for "Nagano Prefecture SDGs promotion company"
2020 Established Rosies Base Inc. as a subsidiary
Invested in affiliated company Henry Monitor Inc.


Head Office / Plant


942-2 Shiga Suwa-City, Nagano Prefecture JAPAN

How to get to Komatsu

By Car
5 min from Suwa-IC of Chuo Expressway
By Train
10min Taxi Ride from Kamisuwa Station or Chino Station


Komatsu Seiki (Thailand) co., Ltd. (KSTh)

Company Name Komatsu Seiki (Thailand) co., Ltd. (KSTh)
Established August 5th, 2002
Location 500/17 Moo 3, T.Tasit, A.Pluakdaeng, Rayong 21140, Thailand
Capital 140 million Baht (THB)
Board Member President and CEO Hisayuki Kasahara
Number of Employees 700 Employees
Amount of Sales 1.56 billion Baht (THB) [2021FY]
Business Content Manufacturing of Fuel Injection Equipment parts for Automobiles, manufacturing of Fuel Injection Equipment parts
Major Trading Bank Sumitomo Mitsui Banking Corporation, Mizuho Bank
ISO ISO9001: 2015
ISO14001: 2015 certification acquisition

nano grains Co., Ltd.

Company Name nano grains Co., Ltd.
Established November 1st, 2013
Location 3-15 Okitamachi, Suwa City, Nagano Prefecture 392-0013
Frontier Building 5th floor
Board Member President and CEO Takafumi Komatsu
Business Content nanoSUS® (ultrafine grain stainless steel), medical device parts development
ISO ISO13485:2016 certification acquisition

Rosies Base Holdings

Company Name Rosies Base Holdings
Established June 1st, 2020
Location One Broadway, 14th Floor Cambridge, MA 02142(USA)
Board Member President and CEO Takafumi Komatsu
Vice President Fumie Yusa
Business Content Research on bio-related evaluation of nanoSUS® (ultrafine grain stainless steel) and development in medical devices


Inquiries by Phone or Fax

Please feel free to contact us for any inquiries regarding technology or products.

  • TEL +81-(0)266-52-6100
  • FAX +81-(0)266-58-1796

Inquiries from the Web

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