Upregulation or downregulation of microRNAs (miRNAs) has been identified in human cervical cancer (CC). However, the character and function of miR-378 in CC remains unknown. In the present study, the authors demonstrated that miR-378 was upregulated in CC used the reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) assay, and promoted cell proliferation by accelerating the progress of cell cycle and repressing cell apoptosis in CC cells. The predicted target genes of miR-378 were determined by enhanced green fluorescent protein (EGFP) reporter assays, RT-qPCR assay and western blot analysis. miR-378 suppressed the expression of suppression of tumorigenicity 7-like (ST7L) by targeting the 3'-untranslated region (3'-UTR) of ST7L mRNA in HeLa and SiHa cells. ST7L was downregulated in CC using the RT-qPCR assay, and the malignant phenotype of HeLa and SiHa cells were inhibited by ST7L overexpression. In addition, miR-378 activated the Wnt/β-catenin pathway by targeting ST7L in CC cells. In short, miR-378 functions as an onco-miRNA by directly downregulating ST7L mRNA and protein level in HeLa and SiHa cells, and serves important roles in the malignancy of CC.