Three new and two known taxane diterpenoids were isolated from the seeds of the Japanese yew, Taxus cuspidata Sieb. et Zucc, and the structures were established as 1 -deoxy-2-O-acetyltaxine B (1 ), 1 -deoxy-2,9-0-diacetyl- 10-deacetyltaxine B (2), 2-0-deacetyl taxine I1 (3), I-deoxy-2,9-O-diacetyltaxine B (4), and 2'-hydroxytaxine I1 (5) respectively on the basis of spectroscopic analysis and comparison of their spectral data with taxine B, of which 1-3 are new.