Karl Slym, managing director of India's Tata Motors, died on Sunday after falling from a high floor of a hotel in Bangkok, the company said.
Slym, 51, had attended a board meeting of Tata's Thailand unit in the Thai capital, a company spokeswoman said, giving no further details. A post-mortem report is due on Monday, she said.
A native of Britain, Slym was hired in 2012 to revive flagging sales and market share in the domestic business of India's biggest automaker, which is part of the Tata conglomerate.
"His death comes at a time when the company seems to be close to turning the corner, with new designs and a new petrol engine family, which hasn't been Tata's strong point," said Anil Sharma, an analyst with IHS Automotive.
Tata Motors recently introduced a new petrol engine for its passenger vehicles and has been planning to launch a new hatchback and compact sedan this year, its first new branded passenger vehicles since 2010.
"It (his death) comes before his efforts bear fruit. We should be able to see the results of his work in a year or two," Sharma said.
Slym led the automaker's operations in India and international markets including South Korea, Thailand and South Africa, excluding the Jaguar and Land Rover (JLR) luxury unit that it acquired in 2008.
Slym "was providing leadership to the company through a challenging market environment", the company said in a statement on Sunday.
Tata Motors had lost traction in its passenger vehicle market as its domestic and foreign rivals rolled out new models while it mostly tweaked existing models and offered heavy price discounts.
The firm has not had a hit car at home since its Indica launch in 1998. Sales of the Nano, the world's cheapest car which it unveiled in 2008, have been lackluster.
Before joining Tata Motors, Slym was executive vice president of SGMW Motors, China, a General Motors joint venture. Before that he had headed General Motors in India.