This study aims to report three new species of Conoideocrella and Moelleriella from Yunnan Province, Southwestern China. Species of Conoideocrella and Moelleriella parasitize scale insects (Coccidae and Lecaniidae, Hemiptera) and whiteflies (Aleyrodidae, Hemiptera). Based on the phylogenetic analyses of the three-gene nrLSU, tef-1α, and rpb1, it showed one new record species (Conoideocrella tenuis) and one new species (Conoideocrella fenshuilingensis sp. nov.) in the genus Conoideocrella, and two new species, i.e., Moelleriella longzhuensis sp. nov. and Moelleriella jinuoana sp. nov. in the genus Moelleriella. The three new species were each clustered into separate clades that distinguished themselves from one another. All of them were distinguishable from their allied species based on their morphology. Morphological descriptions, illustrations, and comparisons of the allied taxa of the four species are provided in the present paper. In addition, calculations of intraspecific and interspecific genetic distances were performed for Moelleriella and Conoideocrella.