Wilms' tumor (WT) is the most common kidney tumor of children. The transformation suppressor gene RECK, which codes membrane-anchored glycoprotein, frequently downregulates multiple matrix metalloproteinases in tumors. And curcumin, which is a polyphenlic compound separated from turmeric, has antitumor effects on various cancers. However, the correlation of WT, RECK and curcumin is still unrevealed. In this study, we evaluated that the methylation degree of RECK was much higher in WT than in adjacent non-tumor tissues. And RECK methylation was closely associated with tumor metastasis in WT patients. After curcumin treatment, the level of RECK methylation was decreased significantly. And the expression of MMP2 and MMP9 was reduced consequently. Moreover, the proliferation, invasion and migration ability of WT cells were suppressed after curcumin treatment. Meanwhile, the apoptosis rate of WT cells was increased simultaneously. In nude mice model, curcumin restrained ability of tumorigenicity and promoted apoptosis of WT cells. Together, our results suggest that the RECK methylation can serve as a prognostic biomarker of WT. Moreover, curcumin could inhibit RECK methylation, thereby abates the expression of MMPs, and suppresses the tumor progression and metastasis of WT.