Four morphologically allied species of the Bradysia hilaris group were studied from China. In a DNA metabarcoding based dipteran diversity study in Zhejiang, eastern China, a hyper-abundant sciarid species was discovered. It was further recognized in this study to be new to science, Bradysia tianmuensis Du & Huang sp. nov., as well as a morphologically similar species, Bradysia curvula Du & Huang sp. nov. Both new species were found to be fairly similar morphologically to the holotype of Bradysia noduspina Yang, Zhang & Yang, 1993 from Guizhou in western China. However, the paratype of B. noduspina appeared to be different from the holotype and determined to be new to science, Bradysia chikunae Du & Huang sp. nov. A phylogenetic tree of all the available 31 COI sequences of the Bradysia hilaris group was provided. Molecular work conducted in the current study also supports Bradysia tianmuensis Du & Huang sp. nov. and Bradysia curvula Du & Huang sp. nov. as new to science thus the four species were described or redescribed accompanied by detailed imagery of habitus and other characters useful for determination.