This experiment was conducted to find out the effects of L-phenylalanine on the saikosaponin content of callus induced from Bupleurum falcatum leaf segments. In the fresh and dry weight of callus, the addition of 2,4-D than L-phenylalanine was significantly effective. However, the L-phenylalanine treatment rather than 2,4-D was effective for high saikosaponin accumulation in the callus of Bupleurum falcatum.