Four lignanamides, a tyramine derivative, and 10 other nonalkaloidal components were isolated from the seeds of Hyoscyamus niger. Among them, hyoscyamide (1), 1,24-tetracosanediol diferulate (6), and 1-O-(9Z,12Z-octadecadienoyl)-3-O-nonadecanoyl glycerol (7) are new structures. The other compounds were identified as grossamide, cannabisin D, cannabisin G, N-trans-feruloyl tyramine, 1-O-octadecanoyl glycerol, 1-O-(9Z,12Z-octadecadienoyl) glycerol, 1-O-(9Z,12Z-octadecadienoyl)-2-O-(9Z,12Z-octadecadienoyl) glycerol, 1-O-(9Z,12Z-octadecadienoyl)-3-O-(9Z-octadecenoyl) glycerol, rutin, vanillic acid, beta-sitosterol, and daucosterol. Grossamide, and cannabisins D and G exhibited moderate cytotoxicity in cultured LNCaP human prostate cancer cells.