The genus Trichopsomyia Williston, 1888 is recorded for the first time from Iran. Trichopsomyia flavitarsis (Meigen, 1822) and T lucida (Meigen, 1822) were determined based on the material collected from a wetland in Aynali forests in 2010. A key to the species of the genus in northwestern Iran is prepared and photographs of the specimens are provided.