A large number of tourists were evacuated, with several suffering from smoke inhalation.
The blaze was brought under control after about an hour.
All 178 rooms at the hotel were reportedly occupied at the time of the fire, mostly by foreign tourists, The Pattaya Mail reported.
Witnesses described scenes of confusion and fear as guests fled through smoke-filled corridors while rescue teams searched the hotel floor by floor for anyone trapped inside, according to Pattaya Mail.
Four people were injured, including two Thai women and an Indonesian boy, while a Thai man suffered burns over about 20% of his body after reportedly running through flames in an attempt to escape.
