The viral video, narrated in Chinese, alleges that Thai immigration officers could be bribed to gain entry into the country and even provide assistance with luggage.
On Monday Maj Gen Choengron Rimpadee, chief of Immigration Division 2 at Suvarnabhumi Airport, was quoted by Nation Thailand as saying the video was recorded inside the airport's arrival hall.
The officer featured in the clip has been identified as Eknarin Chantamatharapaskul, deputy inspector of the inbound immigration unit.
He said the Chinese tourist approached him for help to complete the online entry form, saying he had difficulty understanding the system, and he assisted him.
The tourist later asked for faster passport processing, citing some urgency, but Chantamatharapaskul claimed he directed him to the regular passport queue and resumed assisting other travelers, unaware he was being filmed from behind.
Chantamatharapaskul said he was shocked to learn the video footage had been misused with false claims.