The effects of five lupane-triterpenoids from leaves of two Acanthopanax spp., chiisanogenin, chisanoside and $22{alpha}-hydroxychiisanogenin$, acakoreoside A and acantrifoside A on the mitogen-induced proliferation were investigated in vitro. T cell proliferation (TCP) to concanavalin A (Con A) and the B cell proliferation (BCP) to lipopolysaccharide (LPS) were increased by chiisanogenin. TCP to Con A was significantly increased by chiisanoside and acankoreoside A, but not affected by chiisanogenin, $22{alpha}-hydroxychiisanogenin$ and acantrifoside A, BCP to LPS was significantly increased by acankoreoside A and acantrifoside A, and slightly increased by chiisanoside, chiisanogenin and $22{alpha}-hydroxychiisanogenin$.