Abstract: AIM: A series of Schiff bases of 2-indolaldehyde were synthesized in order to find compounds with anticancer or other biological activities by screening in vitro. METHODS: Electrophilic-substitution, reduction, oxidation and nucleophilic-addition reaction were used in the synthesis of title compounds. RESULTS: Twenty-two compounds were synthesized. The structures of the derivatives were confirmed by ¹HNMR,　MS and elemental analysis data. Compounds 5 and 14 showed inhibitory effects on KB cell line in vitro. CONCLUSION: Some compounds showed anticancer activities and it is worth further studying.