It was the second mishap in less than two weeks for Thailand's national carrier.
After the accident, workers on a crane blacked out the Thai Airways logo on the tail and body of the aircraft in an apparent effort to protect the airline's image. An airline official, Samud Poom-On, said the move was normal practice for Thai Airways after an accident.
Samud initially said the practice was mandated by Star Alliance, but later said that was not the case. The global airline grouping also said it had no such policy.
The flight from Guangzhou, China, was carrying 288 passengers and 14 crew members.
"After touchdown at Suvarnabhumi Airport, the landing gear malfunctioned and caused the aircraft to skid off the runway," Thai Airways President Sorajak Kasemsuvan said in a statement. "Sparks were noticed from the vicinity of the right landing gear near the engine; the matter is under investigation."
Airbus spokesman Justin Dubon said it was too early to comment on what caused the accident. He said Airbus has dispatched a team of experts to Bangkok to aid in the investigation.
Photos taken after the incident showed deep furrows from skid marks on the runway and in a grassy area off the runway, and the aircraft resting with its nose down and emergency slides inflated.
"The captain took control of the aircraft until it came to a complete stop and passengers were evacuated from the aircraft emergency exits," the Thai Airways president said.
A Thai Airways official said 13 passengers were injured, but an airline statement later said 14 passengers had been hurt during the evacuation. It said two of those injured remained at a Bangkok hospital late Monday.
The incident occurred less than two weeks after 20 passengers were injured when a Thai Airways Airbus A380 hit severe turbulence as it was descending to Hong Kong's airport.
Take ABC13 with you!
Download our free apps for iPhone, iPad, and Android devices