Silkworm (Bombyx mori) droppings were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned successively with EtOAc, n-BuOH, and $H_2O$. Three lipids were isolated from the EtOAc fraction by repeated silica gel and ODS column chromatography. Physico-chemical data including NMR, MS, and IR indicated that the isolated lipids were $eta$-sitosterol (1), corchorifatty acid E methyl ester (2), and (8E)-10-hydroxydec-8-enoic acid methyl ester (3). Compounds 2 and 3 have, prior to this study, not previously been documented in nature.