The anti-HIV-1 effects of 204 crude drugs of common use in Japan were evaluated in vitro. As a result, 45 samples inhibited HIV-1-induced cytopathogenicity in MT-4 cells. In particular, the hot water extracts of Lithospermum erythrorhizon (root) and Prunella vulgaris (spike) showed the strongest anti-HIV-1 activities. Their IC100 values were both 16 micrograms/ml. In general, the hot water extracts of the crude drug suppressed the replication of HIV-1 growth more strongly than the cold water extracts.