The 28 species of ten genera, subfamily Phytomyzinae, have been known in Thailand, are revised; 13 new species are described, Phytobia bimaculata sp. nov., P. caudata sp. nov., P. conigera sp. nov., P. cucullata sp. nov., P. papillata sp. nov., P. sinuosa sp. nov., P. thaiensis sp. nov., P. torulosa sp. nov., Amauromyza ramosa sp. nov., Cerodontha triangularis sp. nov., Phytoliriomyza cheliloba sp. nov., Calycomyza flavoscutellata sp. nov., and Aulagromyza mesophalloides sp. nov.; nine Oriental species are recorded as new to the fauna, and one new synonym, Pseudonapomyza rampae Spencer, 1986, is established. Keys to the Thailand species of the genera Phytobia, Cerodontha, Liriomyza and Pseudonapomyza, and keys to the Oriental species of the genera Amauromyza and Aulagromyza are given. 論文 Article