The chalcid wasps (Hymenoptera: Chalcidoidea) is one of the largest groups of wasps with tremendous morphological, ecological, biological, and taxonomic diversity whose economic importance is being pest natural enemies or plant pests. The unknown chalcid fauna of Khuzestan province in southwestern Iran generated the execution of a faunistic study to elucidate its chalcidoid biodiversity. The material was collected by sweeping and trapping during 2014- 2015 from fields, ranges and grasslands. This contribution lists 56 species belonging to 35 genera and 11 families (Agaonidae, Aphelinidae, Chalcididae, Encyrtidae, Eulophidae, Eupelmidae, Eurytomidae, Mymaridae, Pteromalidae, Signiphoridae and Trichogrammatidae). Eupristina saundersi Grandi, 1916 (Agaonidae) and Dirhinus bakeri (Crawford, 1914) (Chalcididae) are new records for the fauna of Iran, while Euplectrus liparidis Ferrière, 1941 and Hemiptarsenus zilahisebessi Erdös, 1951 (Eulophidae), Eupelmus sp. (Eupelmidae) and Mymar taprobanicum (Ward, 1875) and Polynema sp. (Mymaridae) are new for the Khuzestan province fauna.