An investigation of a questionable species of the genus Alseodaphne led to the discovery of a new genus Alseodaphnopsis H.W.Li \&J.Li,gen.nov., separated from Alseodaphne Nees, and a new species Alseodaphnopsis ximengensis H.W.Li \& J.Li,sp.nov., endemic to Yunnan province, China. This new species is characterized by having big, axillary, paniculate inflorescences, as well as large, subglobose fruits. Based on DNA sequence data from two gene regions (nuclear ribosomal ITS and LEAFY intron II), we investigate its phylogenetic position within the Persea group. Phylogenies using maximum parsimony (MP) and Bayesian inference (BI) support the recognition of Alseodaphnopsis as a distinct genus but do not resolve well its relationship within the Persea group. The new genus is circumscribed, eight new combinations for its species are made, and a description and illustration of the new species are provided.