Two novel alkaloids, leucotamine (1) and O-methylleucotamine (2), with a 3R-hydroxybutyryl group, and another new alkaloid, 3-O-acetylungiminorine (3), were isolated from leaves of Leucojum asetivum (Amaryllidaceae) together with five known alkaloids. O-Methylleucotamine (2) and 3-O-acetylungiminorine (3), as well as four known bases, were also isolated from bulbs of this plant. The stereochemistries of the new compounds 1, 2, and 3 were established on the basis of chemical and spectral data.