Bioassay directed fractionation of the (1:1) chloroform-methanol extract of Gentiana spathacea H.B.K (Gentianaceae) led to the isolation of gentiopicroside (gentiopricrin) (1), the major spasmolytic component of the plant. Gentiopicroside inhibited, in a concentration-dependent manner, the spontaneous contractions of isolated guinea pig ileum. Contractions induced by histamine, acetylcholine, BaCl2 and KCl on the ileum were also significantly blocked by this monoterpene glucoside, which suggests that this compound might be interfering with calcium influx into the smooth muscle cells.