MicroRNAs (miRNAs/miRs) serve important roles in regulating malignant phenotype in numerous cancers, such as non-small cell lung cancer (NSCLC); however, the role and function of miR-577 in NSCLC remains unknown. In the present study, miR-577 expression levels were observed to be downregulated in NSCLC via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay, and inhibited cell proliferation, cell migration and invasion and epithelial-mesenchymal transition progress in NSCLC cells. The predicted target genes of miR-577 were determined by enhanced green fluorescent protein reporter assay, RT-qPCR and western blot analyses. miR-577 was demonstrated to suppress the expression of WNT2B by targeting the 3'-untranslated region of WNT2B mRNA in H522 and A549 cells. WNT2B was upregulated in NSCLC cells as observed via RT-qPCR analysis, and the malignant phenotype of H522 and A549 cells were promoted by WNT2B overexpression. In addition, miR-577 inactivated the Wnt/β-catenin pathway by targeting WNT2B in NSCLC cells. Collectively, miR-577 may function as a suppressor gene by directly downregulatingWNT2B mRNA and protein expression levels in H522 and A549 cells, and may serve important roles in the malignancy of NSCLC.