The Football Association of Thailand has suspended referee Somsak Poosomnuek for using a racist insult to Thai-Ghananian player Abdulkordiri Hamid during a third division game, the FAT said on Wednesday.
"The Football Association of Thailand has suspended the referee from all competitions," the FAT said in a statement.
The suspension will remain in place while an investigation is carried out, the statement said.
Hamid's club expressed their support for the player.
"We oppose racism, insults, or insults based on race, religion, or ethnicity," Prachinburi City said.
The referee is accused of using the Thai equivalent of the N-word, and the club said it was "not the first time" the player had faced such remarks on the pitch.
On his personal Facebook page, Hamid posted: "I can speak Thai ... Since you are a referee, you should be calling me with a better word."
Hamid, who speaks fluent Thai, said the referee made the remarks to him during a Thai League 3 match on Sunday.