Japan, Manchuria, and Thailand (12) used the Ki-27.
The Ki-27 first arrived in China in March 1938. In the CBI (China Burma India) theater the Ki-27 was known as the "Abdul."
Against Russia in May - September 1940, during the Nomonham Incident, the Ki-27 pilots claimed 1,340 Russian aircraft shot down. Revised figures place this to be actually around 200.
South West Pacific
In December 1941 the Ki-27s supported the Japanese invasion of the Philippines, Malaya Burma, and the Netherlands East Indies.
Once the Ki-27 was withdrawn from front line combat, they were used for defense of the Japanese home islands and training.
As a kamikaze aircraft it could carry a 1,102 lb / 500 kg bomb.