Twenty-four diosgenyl saponins bearing cinnamoyl, carbamido and thiosemicarbazone groups were synthesized concisely. The cytotoxicities of the synthetic compounds on six human caner cell lines were evaluated employing MTT method. Structure-activity relationship could be observed, and two of the synthesized compounds (5c and 5f) exhibited selective inhibition on HeLa and MCF-7 cells, while three of them (5d, 5f and 5h) showed strong inhibition against HT1080.