Using cholesterol, β-sitosterol, dehydroisoandrosterone and pregnenolone as starting materials, a series of 6- hydroximino analogs of ring B abeo-sterols were synthesized and characterized. The antiproliferative activity of analogs was evaluated against SGC 7901 (human gastric carcinoma), HeLa (human cervical carcinoma) and Bel 7404 (human liver carcinoma) cells. The results showed that the presence of a alkyl side chain was very important for their cytotoxicity. However, the presence of 6-hydroximino cannot increase the cytotoxicity of compounds compared with 6-hydroxy group. The information obtained from the studies may be useful for the design of novel chemotherapeutic drugs.