Police said more bodies may be inside, and firefighters continued searching through the smoke-filled 450-room Royal Jomtien Resort on Jomtien Beach, 110km (68 miles) south of Bangkok.
Survivors said they heard no fire alarms, the hotel apparently had no sprinklers, and emergency exits were found locked.
Firefighters had the blaze under control by mid-afternoon, but took until 9pm to extinguish it. Rescue workers used cranes and floodlights through the night to search the top storeys.
The Thai Interior Minister, Snoh Thienthong,, blamed the high number of fatalities on hotel operators who locked emergency exits to prevent customers from leaving without paying.
Police said many of the bodies were found near the locked emergency doors. In addition to the dead, at least 64 people were injured. Many were seriously burned.
Police said eight Westerners were among the dead, but could identify them only as five men and three women.
More than 30 Thais killed have so far been identified, including 17 employees of the state-owned Electricity Generating Authority of Thailand and several members of the local subsidiary of Pepsico, who were attending seminars at the hotel. Eleven hotel workers also perished.
The fire started at about 9am when a gas oven exploded in a first floor coffee shop, police said. It quickly spread to other floors, searing black burn marks into the building's white facade from the ground floor to the roof.
Hundreds of people watched from the pavement as people screamed for help and waved towels from windows on the upper floors. A man jumped from an 11th-floor window to avoid the flames, and died. Rescue workers carried out dozens of charred, blackened bodies.
The black plume of smoke stretched far above the white sand beach as three police helicopters, navigating their way through it, plucked terrified guests from the hotel roof.
Rescue teams on the roof dropped harnesses down to guests who made it to the top floor and were crying for help from windows as smoke billowed out behind them.
Rochelle Stein-Sami, an American, told ITV television that no smoke alarms sounded, no sprinklers went off and there were no warnings of any kind. The mayor of Pattaya, who called the fire the city's worst tragedy, also said the hotel did not have sprinklers.
Ms Stein-Sami was able to use her mobile phone to call from her top-floor room to a friend on the street standing next to police. They told her helicopters were on the way.
Television crews filmed her daughter as she was lifted in a harness, still clutching her brown teddy bear, to rescue workers on the roof and bundled into a helicopter.
Firefighters siphoned water from the hotel pool to fight the blaze, which is thought to have caused at least $40m (pounds 24m) in damage.
Earlier this year, Prime Minister Chavalit Yongchaiyudh called Pattaya "Thailand's greatest source of evil."
Bangkok has had a high number of hotel and department store fires in recent years. Fire safety experts in Thailand say many buildings don't meet basic safety standards.
In 1993, 188 people died in a fire at the Kader Toy factory in the north- east. Police said factory supervisors had locked emergency exits to prevent workers from taking breaks.Reuse content