Colorectal cancer remains one of the most common cancers in men and women, and it accounts for a large proportion of cancer-related deaths worldwide. Tripartite motif (TRIM) proteins are a novel class of "single protein RING finger" E3 ubiquitin ligases, which have been shown to be involved in many cancers. The aim of this study was to investigate the potential role of TRIM24 in human colorectal cancer. By using a lentivirus-mediated RNA interference system, we first explored the effect of TRIM24 knockdown on HCT116 cell proliferation and colony formation. Moreover, flow cytometry analysis was used to examine its effects on cell cycle distribution and apoptosis. Our data showed that knockdown of TRIM24 expression in HCT116 cells significantly decreased cell growth due to the induction of apoptosis. Hence, the present study provides evidence that TRIM24 functions as an oncogene in colorectal carcinogenesis.