Toyota has invested hundreds of millions of dollars in Pony.ai since the companies first teamed up in 2019.
Pony.ai CEO Peng Jun said the move would support the development of the connected car industry.
China has been at the forefront in the development of self-driving cars and Pony.ai has launched robotaxi services in Beijing, Shanghai, Shenzhen and Guangzhou. The company also has offices in the United States.
Automakers outside China have, however, retreated from ambitious rollout schedules predicted a few