Corporate Profile

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Opening the Future Together
with Technology and Quality

Since our founding in 1960, we have been involved in the processing of precision parts used in automobile footholds. Our products are very important products used in automobiles carrying human lives. For this reason, we are constantly working to innovate and improve quality with a sense of tension and responsibility that entrusts many human lives who use the products of automakers that are our customers.

The industry related to the automobile industry is expected to change rapidly in the future and competition will become increasingly intense. That is why we will boldly take on new challenges and grow faster than ever to continue providing the highest quality products that meet the needs of our customers.

As a member of society, we are also involved in activities aimed at sustainable development, such as efforts to curb global warming and protect the environment. We will also fulfill our social responsibilities as a company through contributions to local communities.

In order to continue to contribute to local communities and customers, we will innovate in technology, provide products of the quality demanded by society, and work together to cultivate our future.

Representative Director and President石黒 和之

Representative Director and President

石黒 和之


  • Founding spirit
    "Together with Our Employees, Together with Our Customers, Together with Society" will lead to prosperity.
  • Management Philosophy
    Through work that pleases our customers,
    By realizing both the physical and mental happiness of all employees,
    We will provide safety and security to our customers and contribute to the development and prosperity of the world.
  • Action Guidelines
    1. Work that is valued by customers and that is useful and valuable to society.
    1. We will act vigorously, positively, and brightly.
    1. We will always take on the challenge of positively thinking and innovate.
    1. Acquire good habits and improve professional knowledge and skills.

Policies on environmental protection

Acquired ISO 14001 certification
In 2015, we acquired international standards for environmental management systems.
Recognizing that the conservation of the global environment is one of the most important issues common to all mankind, we are continuously working to reduce the burden on the environment and develop resource-recirculating products from a global perspective, taking advantage of our integrated production technology from cold forging to assembly, which is our characteristic. As a corporate citizen that constitutes society, we are actively engaged in activities to curb global warming and environmental conservation activities.

Quality Policy

Acquired IATF16949 certification
In 2016, we acquired international standards for quality management systems specializing in the automotive industry.
In order to improve customer satisfaction,we strive to accurately understand customer needs,supply products that satisfy demands in a timely manner,conduct activities to achieve our PDCA and continuously improve them,and promote quality improvement activities aimed at quality No.1.

Health and Productivity Management Policy

Acquisition of Health Excellent Company Certification (Silver Certification Certificate)
In April 2023, we were certified as an excellent health-conscious company (silver certification) by working to improve the health of the workplace and the workplace environment where employees can work in good health, and promote health throughout the company.
We will continue to put the health of our employees first by creating a workplace where everyone can work with enthusiasm.

Corporate Profile

  • Company name
    Kyoritsu Seiki Co., Ltd.
  • Representative of director
    Kazuyuki Ishiguro
  • Head Office Location
    1515, Makabe, Soja City, Okayama Prefecture 719-1134
  • TEL
  • Capital
    70 million yen
  • Description of business
    Development and manufacturing of automotive parts by cold forging (such as ball joints, stabilizer links, locking bases, etc.)
  • Number of Employees
    170 (April 1, 2023)
  • Major Business Partners (50 sound order)
    Joisson Safety Systems Japan Inc.
    Sterantis Inc.
    Nissan Motor Co., Ltd.
    Mitsubishi Motors Corporation
    Mitsubishi Electric Corporation
    Mitsubishi Fuso Truck and Bus Corporation, etc.

Company History

  • 1960
    Founded in Fukuyama City, Hiroshima Prefecture
  • 1961
    Kyoritsu Seiki Mfg. Co., Ltd. established
  • 1965
    Relocated to 1515, Makabe, Soja City, Okayama Prefecture (Mizushima Machinery & Metals Industrial Park)
  • 1984
    Kyoritsu Seiki Mfg. Co., Ltd. changed its name to Kyoritsu Seiki Co., Ltd.
  • 1986
    Setsuko Ishiguro was appointed President
    Started operation of plant exclusively for spool valves
  • 1987
    Established Nippon EWI Co., Ltd.
    Joint investment to establish EWI in Illinois, U.S.
  • 1988
    Established BEW Co., Ltd. in Bangkok, Thailand as a joint investment.
  • 1989
    Constructed a third plant in the West of Wing Valley Complex in Kushiro, Soja CityAcquired the former Sen Electric production site.
  • 1999
    Acquired the former Sen Electric production site.
  • 2000
    Kazuyuki Ishiguro became representative of director
  • 2003
    Head Office | Acquired 5th Factory
    Started manufacturing CVT components
  • 2004
    Invested in Shinsei EWI Co., Ltd.
  • 2005
    Established KYORITSU SEIKI AMERICA Inc. as a locally-incorporated company in Detroit, Michigan, USA
  • 2011
    Kyoritsu Seiki (Thailand) Co., Ltd. established in Thailand


  • Head Office & 1st Factory

    1515 Makabe, Soja-City, Okayama 719-1134, JAPAN.


  • 2nd Factory

    1482 Makabe, Soja-City, Okayama 719-1134, JAPAN.


  • 3rd Factory

    1408-5 Hisayo, Soja-City, Okayama 710-1201, JAPAN.



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