Solanum lyratum, a rare species, is used to treat cancer, tumors and warts. Plant cell- and tissue-culture of S. lyratum, producing steroidal alkaloids, could be useful supplements to natural sources. We previously showed that a culture system of its cells could produce steroidal alkaloids. The purpose of this study was to study the production of solanine, solanidine, and solasodine by adding auxin-type phytohormones including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D) to cell and callus cultures of this species. 2,4-D-induced calli from roots led to a significant enhancement in solanine production with a value of 4.13 mg/g dry weight (DW). The maximal solanidine and solasodine levels of 6.26 and 7.69 mg/g DW were respectively obtained with IBA- and IAA-treated S. lyratum cells at concentrations of 1 and 5 mg/l.