We revealed that, as an oncogenic gene, miR-214-3p targets 3ꞌ-UTR of the DKK3 to degrade it, which causes an accumulation of the active β-catenin in cytoplasm of osteosarcoma cells and leads to an increased β-catenin nuclear translocation to further activate LEF1 translation, as a result, Wnt/β-catenin signaling is activated to promote osteosarcoma progression. This evidence concerns the gene LEF1 and osteosarcoma.