Komatsu Iron Works was started by Takeuchi Mining Industry as a subsidiary to make industrial tools for the parent company.
 Komatsu eventually became large enough to sell to the public, and was spun off on May 13, 1921 as Komatsu Ltd and founded by Meitaro Takeuchi.

Komatsu produced its first agricultural tractor prototype in 1931.
 Through the 1930s, Komatsu also produced tractors for the Japanese military, as well as bulldozers, tanks and howitzers.
 After World War II, under its new president Yoshinari Kawai, Komatsu added non-military bulldozers and forklifts to its line of equipment.
 In 1949 it began production of its first diesel engine.
 Its growth as a company was aided by the strong demand for its bulldozers during Japan's post-war reconstruction in the 1950s.
 In August 1951 the corporate headquarters were moved to Tokyo.
By 1957 the company had advanced technologically to the point that all its models were using Komatsu engines.

In 1964, Rioichi Kawai, son of Yoshinari Kawai, became president of Komatsu, and it began exporting its products, looking to counteract the postwar image of Japanese products as being cheap and poorly made.
In July 1967, it entered the U.S. market, taking on Caterpillar, the largest bulldozer maker, in its home market.
 This was done under the company slogan of "Maru-C", translating into English as "encircle Caterpillar" (from the game of Go (board game), where encircling an opponent results in capture of his territory).

Expansion overseas was a major focus in the 1970s, with Komatsu America Corporation being established in February 1970 in the United States.
 A year later, in January 1971, Komatsu Singapore Pte.
Ltd. was established in Singapore.
 September 1974 saw the founding of Dina Komatsu Nacional S.A. de C.V., a joint venture with truck maker DINA S.A. in Mexico.
 April 1975 was the founding Komatsu do Brasil Ltda.
in Brazil.
 This company produced the Komatsu D50A bulldozer, marking Komatsu's first offshore production of construction equipment.
 Komatsu Australia Pty.,
Ltd. in Australia was established in Feb. 1979.

In the 1980s, Komatsu and International Harvester of the United States had a joint venture to produce compact tractors called KIMCO.

In 1982, PT Komatsu Indonesia was founded and production began in 1983 in Indonesia.
 Two divisions in the United States were established for manufacturing in 1985, Komatsu America Manufacturing Corp. and Komatsu America Industries LLC.
 Komatsu Industries Europe GmbH was set up in 1986 in Germany.

In 1987, Komatsu and BEML formed a joint-venture known as BEML Komatsu.

Komatsu and Dresser Industries established Komatsu Dresser to make mining tractors and related equipment in 1988.
 This 50-50 ownership lasted from September 1988 to August 1994, when Komatsu bought out Dresser's share.
Komatsu's mining products were consolidated under the name Komatsu Mining Systems in 1997.
 To prevent brand-name confusion during these corporate changes, the name "Haulpak" was used for the product line Komatsu began with Dresser.
The name "Haulpak" dates back to 1957 when LeTourneau-Westinghouse introduced a range of rear dump trucks known as "Haulpaks".
LeTourneau-Westinghouse equipment later became known simply as WABCO equipment in 1967.
The name Haulpak was an industry term that eventually became applied to any type of rear dump truck.
A detailed history of the development of the Haulpak can be found in Wabco Australia.

In 1989, Komatsu bought a share of Hanomag AG and since 2002 Komatsu Hanomag GmbH has been a 100% subsidiary of the global company.

During the 1990s Komatsu had a joint venture in Europe with Moxy were Komatsu designed Articulated Dump Truck were built under license for the European market by Moxy. (
In 2008 Moxy was taken over by Doosan of Korea.)

FAI of Italy was invested in during 1991.
As Komatsu's equity increased, the company was renamed in 1985 to FKI Fai Komatsu Industries S.p.
A., which was then renamed in 2000 to Komatsu Utility Europe S.p.
A. when Komatsu assumed 100% ownership.

Komatsu owns the former Demag range of Mini
Komatsu Iron Works was started by Takeuchi Mining Industry as a subsidiary to make industrial tools for the parent company.  Komatsu eventually became large enough to sell to the public, and was spun off on May 13, 1921 as Komatsu Ltd and founded by Meitaro Takeuchi.
Komatsu produced its first agricultural tractor prototype in 1931.  Through the 1930s, Komatsu also produced tractors for the Japanese military, as well as bulldozers, tanks and howitzers.  After World War II, under its new president Yoshinari Kawai, Komatsu added non-military bulldozers and forklifts to its line of equipment.  In 1949 it began production of its first diesel engine.  Its growth as a company was aided by the strong demand for its bulldozers during Japan's post-war reconstruction in the 1950s.  In August 1951 the corporate headquarters were moved to Tokyo. By 1957 the company had advanced technologically to the point that all its models were using Komatsu engines.
In 1964, Rioichi Kawai, son of Yoshinari Kawai, became president of Komatsu, and it began exporting its products, looking to counteract the postwar image of Japanese products as being cheap and poorly made. In July 1967, it entered the U.S. market, taking on Caterpillar, the largest bulldozer maker, in its home market.  This was done under the company slogan of "Maru-C", translating into English as "encircle Caterpillar" (from the game of Go (board game), where encircling an opponent results in capture of his territory).
Expansion overseas was a major focus in the 1970s, with Komatsu America Corporation being established in February 1970 in the United States.  A year later, in January 1971, Komatsu Singapore Pte. Ltd. was established in Singapore.  September 1974 saw the founding of Dina Komatsu Nacional S.A. de C.V., a joint venture with truck maker DINA S.A. in Mexico.  April 1975 was the founding Komatsu do Brasil Ltda. in Brazil.  This company produced the Komatsu D50A bulldozer, marking Komatsu's first offshore production of construction equipment.  Komatsu Australia Pty., Ltd. in Australia was established in Feb. 1979.
In the 1980s, Komatsu and International Harvester of the United States had a joint venture to produce compact tractors called KIMCO.
In 1982, PT Komatsu Indonesia was founded and production began in 1983 in Indonesia.  Two divisions in the United States were established for manufacturing in 1985, Komatsu America Manufacturing Corp. and Komatsu America Industries LLC.  Komatsu Industries Europe GmbH was set up in 1986 in Germany.
In 1987, Komatsu and BEML formed a joint-venture known as BEML Komatsu.
Komatsu and Dresser Industries established Komatsu Dresser to make mining tractors and related equipment in 1988.  This 50-50 ownership lasted from September 1988 to August 1994, when Komatsu bought out Dresser's share. Komatsu's mining products were consolidated under the name Komatsu Mining Systems in 1997.  To prevent brand-name confusion during these corporate changes, the name "Haulpak" was used for the product line Komatsu began with Dresser. The name "Haulpak" dates back to 1957 when LeTourneau-Westinghouse introduced a range of rear dump trucks known as "Haulpaks". LeTourneau-Westinghouse equipment later became known simply as WABCO equipment in 1967. The name Haulpak was an industry term that eventually became applied to any type of rear dump truck. A detailed history of the development of the Haulpak can be found in Wabco Australia.
In 1989, Komatsu bought a share of Hanomag AG and since 2002 Komatsu Hanomag GmbH has been a 100% subsidiary of the global company.
During the 1990s Komatsu had a joint venture in Europe with Moxy were Komatsu designed Articulated Dump Truck were built under license for the European market by Moxy. (In 2008 Moxy was taken over by Doosan of Korea.)
FAI of Italy was invested in during 1991. As Komatsu's equity increased, the company was renamed in 1985 to FKI Fai Komatsu Industries S.p.A., which was then renamed in 2000 to Komatsu Utility Europe S.p.A. when Komatsu assumed 100% ownership.
Komatsu owns the former Demag range of Mini
Komatsu Limited