Two new species of tetragnathid spiders from Guizhou and Sichuang provinces of China are described: Diphya guiyang J. Zhang & H. Yu, sp. nov. (♂♀) and Diphya weimiani J. Zhang & H. Yu, sp. nov. (♀). Detailed descriptions, diagnoses, and photographs are provided for these two species, as well as a key and a distribution map for Chinese Diphya species. DNA barcodes (a partial fragment of the mitochondrial cytochrome oxidase subunit I gene, COI) of both new species were obtained for species delimitation, matching of different sexes, and future use in molecular studies.