Objective: To investigate whether miR-124 inhibits proliferation and invasion of colon cancer cells by targeted regulation of TET protein family expressions. Methods: The effect of miR-124 on luciferase activity of TET family (TET1, TET2 and TET3) was examined respectively by using a dual-luciferase reporter gene system. The changes in mRNA and protein expressions of TET family in colon cancer HT29 cells after transfection of miR-124 mimics were tested by qRT-PCR and Western blot analysis. The changes in proliferative and invasion abilities of HT29 cells after transfection of miR-124 mimics or TET siRNAs were determined by MTS and Transwell assay, respectively. Results: The results of the dual-luciferase reporter gene assay demonstrated that the 3’UTR of each TET mRNA was specifically matched by miR-124 and their luciferase activities were significantly inhibited (all P<0.05). The mRNA and protein expressions of TET in HT29 cells were significantly down-regulated after miR-124 mimics transfection (all P<0.05). The proliferative and invasion abilities of HT29 cells were significantly reduced after either miR-124 mimics or TET siRNAs transfection (all P<0.05). Conclusion: MiR-124 inhibits proliferation and invasion of colon cancer cells probably through direct regulation of TET expression.