Chinese Super League champions Guangzhou Evergrande sacked Yu Hanchao and the international winger faces 15 days in police custody after he was spotted altering the licence plate on his Mercedes 4x4.
Guangzhou, who are managed by Italian World Cup winner Fabio Cannavaro, said that the 33-year-old had "severely violated" the club's strict disciplinary code.
Police in the southern city fined Yu 5,000 yuan ($700), added 12 points to his licence and will hold him for 15 days in "administrative detention".
It came after footage emerged on Tuesday of the 59-capped Yu, who has scored nine goals for China, appearing to change a letter E on his registration plate to F for reasons that were not immediately clear.
"Guangzhou traffic police found an illegal traffic safety act of using a modified vehicle number plate," police officials said in a statement on the Twitter-like Weibo.
"After investigation and evidence collection by Guangzhou traffic police, the perpetrator surnamed Yu admitted the illegal facts."
Yu has won the Chinese Super League five times with Guangzhou and lifted the AFC Champions League.