Concert promoter BEC-Tero announced today that the concert was cancelled "due to recent events in Thailand". It called the move "a difficult decision for all parties".
The concert in Bangkok would have been on the night of June 9, but the country is under a night-time curfew.
Swift said: "I'm sending my love to the fans in Thailand. I'm so sad about the concert being cancelled."
The American singer-songwriter has other performances throughout Asia during her current Red Tour.