Aberrant regulation of the Wnt/β-catenin signaling pathway is one of the major causes of colorectal cancer (CRC). In this study, we examined the effect of polymethoxyflavones present in citrus peels on Wnt/β-catenin signaling in the HCT116 CRC cell line. We found that 5,7,3',4'-tetra-methoxyflavone (TMF) and 7,8,3',4'-TMF inhibited the expression of target genes of Wnt/β-catenin signaling and the transcriptional activities of β-catenin/Tcf and suppressed the motility of HCT116 cells. Because the binding of β-catenin to Tcf-4 was disrupted by 5,7,3',4'-TMF and 7,8,3',4'- TMF, we suggest that they are inhibitors of the Wnt/β-catenin signaling and may have potential applications in CRC prevention.