Elevated expression of SMYD3 is a frequent genetic abnormality in several malignancies. Few studies knocking down SMYD3 expression in cervical carcinoma cells have been performed to date. In this paper, we established an inducible short hairpin RNA expression system to examine its role in maintaining the malignant phenotype of HeLa cells. After being induced by doxycycline, SMYD3 mRNA and protein expression were both reduced, and significant reductions in cell proliferation, colony formation and migration/invasion activity were observed in the SMYD3-silenced HeLa cells. The percentage of cells in sub-G1 was elevated and DNA ladder formation could be detected, indicating potent induction of apoptosis by SMYD3 knockdown. These findings imply that SMYD3 plays crucial roles in HeLa cell proliferation and migration/invasion, and that it may be a useful therapeutic target in human cervical carcinomas.