The man was among 25 people (11 men, 14 women) detained when police and local officials raided the Ban Tulip Hotel at about 11.30pm on Saturday (21 Apr).
They were found in a room at the hotel’s ground floor, naked and performing sexual activities.
Besides the Singaporean, others included people from America, Canada, China, Malaysia, Singapore, Germany, Thailand, Cambodia, India and Ukraine.
A local official said that people wanting to go to the party had to sign up via a website and pay 1500 baht (S$62) in admission fees.
The hotel operator, a 53-year-old Chinese national, was arrested for violating the Hotel Act and illegally facilitating sexual activities.