Eleven phenolic compounds including caffeic acid were identified through analyzing the aqueous extracts of Pinus rigida by HPLC. Among them, protocatechuic acid was the maximum amount of 6.84 ppm. Seed germination of Cassia mimosoides var. nomame was significantly stimulated by the extract of P. rigida leaves in the proportion ot concentration. However, root growth was elevalted at a threshold concentration below 25%, but it was inhibited at high concentrations. In 50% extract of P. rigida, upward root tip of C. mimosoides var. nomame showed negageotropism which the root end showed necrosis. New isozyme bands were induced indicating concentration activity of peroxidase from the extract of C. mimosoides var. nomame, especially in the cathodic region. Although it reduced the mumber of isozyme bands of esterase, esterase activities were stimulated in the anodic region of C. mimosoides var. nomame. The activity of amylase was not remarkably different between control and treatment.