Phytochemical investigation of the CHCl3 fraction of Swertia corymbosa resulted in the isolation of a new 3-allyl-2,8-dihydroxy-1,6-dimethoxy-9H-xanthen-9-one (1), along with four known xanthones, gentiacaulein (3), norswertianin (4), 1,3,6,8-tetrahydroxyxanthone (5), and 1,3-dihydroxyxanthone (6).