Phaya Thai is a district in central Bangkok. Neighbouring districts are (from north clockwise), Chatuchak, Din Daeng, Ratchathewi and Dusit.
Phaya Thai District was set up in 1966 by taking areas that were part of Dusit and Bang Kapi Districts. It was named after Phaya Thai Road, its major thoroughfare. Since then, many changes to the district have been made. In 1973, the Huai Khwang District was separated from Phaya Thai. Later in 1978, as an effort to balance the population among districts, the boundaries between Phaya Thai, Huai Khwang, and Bang Kapi Districts were modified. A new Ratchathewi District was created by carving off the southern part of Phaya Thai in 1989. In 1993, some eastern parts were moved out of the district to the newly-formed Din Daeng, leaving Phaya Thai with only one remaining sub-district, Sam Sen Nai.
Due to the split off of Ratchathewi, Phaya Thai Road is no longer in Phaya Thai District. It runs through Ratchathewi and Pathum Wan. Similarly, Phaya Thai BTS Station is in Ratchathewi, on Phaya Thai Road.