We made a trial of searching for the bioactive substances from Sandohnin( ?? ?? ?? ). The blood and bile of rats after the oral administration of extracts of Sansohnin were analyzed by three-dimensional high-performance liquid chromatography (3D-HPLC). In blood, spinosin and feruloyl spinosin were found after the oral administration of a butanol extract of Sansohnin. In bile, spinosin and feruloyl spinosin were also identified after the oral administration of a water extract of Sansohnin. Spinosin and feruloyl spinosin induced the prolongation of hexobarbital sleeping time in mice at doses of 50 and 100 mg/kg, respectively. We concluded that spinosin and feruloyl spinosin were the bioactive constituents of Sansohnin. It was assumed that spinosin and feruloyl spinosin circulated through the intestine and liver, therefore, these results will provide support for the sedative and hypnotic use of this crude drug in Oriental medicine.