A amphoe (sometimes also amphur, Thai: อำเภอ) is the second level administrative subdivision of Thailand. Usually translated as district, amphoe make up the provinces. Amphoe are further subdivided into tambon.

Altogether Thailand has 795 districts and 81 minor districts (King Amphoe, กิ่งอำเภอ). The 50 districts of Bangkok are called khet (เขต), but even in official documents are sometimes misnamed as amphoe. The number of amphoe in a province differs, from only 3 in the smallest provinces up to the 50 urban districts of Bangkok. Also the sizes and population of the amphoe differs, the lowest population is in King Amphoe Ko Kut (Trat province) with just 2042 citizens, while Amphoe Mueang Samut Prakan (Samut Prakan province) has 435,122 citizens. Areawise the khet of Bangkok are the smallest - Khet Samphanthawong is the smallest with only 1.4 km² _ while the amphoe of the low populated mountain regions are bigger than some provinces _ Amphoe Umphang (Tak province) with 4,325.4 km² is the largest.