HTMS Sukhothai was patrolling in the Gulf of Thailand when the warship was caught by rough seas and strong tidal currents and began taking on water.
In dramatic pictures taken by the rescue ships that were sent out, the corvette is seen with a heavy gunwale.
Shortly thereafter, the ship sank.
- We are still looking for 31 missing, says Admiral Pogkrong Montradpalin, the navy's spokesperson.
According to Montradpalin, the ship's operating system stopped working, causing the sailors on board to lose control of the corvette.
75 people were rescued when the HTMS Sukhothai sank in the dark water.
About ten of them are treated in hospital.