Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts that play important roles in tumorigenesis and tumor progression. Our study aimed to explore the role of lncRNA MAGI2-AS3 in breast cancer metastatic progression. In the present study, our results showed that MAGI2-AS3 can inhibit the migration and invasion of breast cancer cells. In addition, an increase in MAGI2-AS3 can inhibit microRNA-374a (miR-374a) expression in breast cancer cells. Bioinformatic analysis predicted the correlation between MAGI2-AS3 and miR-374a. Phosphatase and tensin homolog (PTEN) was found to be an novel mRNA target of miR-374a. MAGI2-AS3 upregulation inhibited breast cancer metastatic progression by decreasing miR-374a and enhancing PTEN expression. Together, our data revealed that lncRNA MAGI2-AS3 is involved in breast cancer cell progression by regulating the miR-374a-PTEN axis. These findings offer new insight into treatment strategies for breast cancer.