Son Jun-ho, who plays in the Chinese Super League, is in police custody in Liaoning province, China's foreign ministry said.
The 31-year-old was detained at a Shanghai airport on Friday, according to South Korean media.
Reports of Mr Son's detention come amid a concerted crackdown on corruption and match-fixing in Chinese football.
Diplomats from South Korea will meet with Mr Son "to figure out exactly what kind of charges" he has been detained for, Yonhap News Agency reported, citing sources.
China's foreign ministry said its mission in China was providing consular support to Mr Son, but declined to comment further.
