A new genus Mengzongella gen. nov. is described to accommodate a new species M. tertia sp. nov. based on two males collected in Guangxi, China, from the leaf litter of a giant bamboo thicket (Bambusa chungii syn. Lingnania chungii). The new genus belongs to the family Urodinychidae based on the shape of the gnathosomal setae h1, shape of the chelicerae and the presence of the cheliceral node. The new genus differs from the previously described ones by deep transversal dorsal furrows, the shape of the dorsal and ventral setae and the undulate inner margins of the marginal shield. Two previously described Japanese species [Urodiaspis sandankyoensis () and Urodiaspis yonakuniensis ()] are transferred to the new genus as Mengzongella sandankyoensis () comb. nov. and Mengzongella yonakuniensis () comb. nov.