In a memo first reported by the news site Electrek, Elon Musk said he was "extremely sorry to be letting staff go but it had to be done".
The world's largest carmaker by market capitalization had 140,473 employees worldwide as of December, according to the latest annual report.
"We took a comprehensive look at the organization and had to make the difficult decision to reduce our headcount by more than 10 percent globally," Musk said.
Tesla has begun to feel the impact of slowing demand for electric vehicles. The company reduced production at the Gigafactory in Shanghai and told employees at Cybertruck that shifts would be shorter on the production line in Austin.
The company is due to release quarterly earnings later this month but reported a drop in vehicle deliveries in the first quarter, the first decline in nearly four years and below market expectations. Some analysts called the results "turbulent".
