Objective To investigate the effect and mechanism of OSTN-AS1 on the proliferation, migration, and invasion of prostate cancer cell PC-3M. Methods The cancerous tissues and corresponding adjacent tissues of 25 prostate cancer patients were collected, and then RT-qPCR was used to measure the expressionof OSTN-AS1 in the tissues. PC-3M cells were transfected with OSTN-AS1 small interfering RNA and / or miR-330 inhibitor. Flow cytometry was used to analyze the cell cycle. A colony formation assay was used to analyze the number of cell clones. Transwell assays were used to analyze the migration and invasion. RT-qPCR was used to measure the expression of miR-330 and MMP-2 mRNA. Dual luciferase reporter gene assays were used to verify the regulatory relationships between OSTN-AS1 and miR-330 as well as miR-330 and MMP-2. Transfected PC-3M cells were injected into nude mice subcutaneously. After 4 weeks, the tumors were harvested and weighed. Results Expression of OSTN-AS1 was increased in prostate cancer tissue (P<0.05), but expression of miR-330 was decreased (P<0.05). Down-regulating OSTN-AS1 blocked cell cycle progression of PC-3M cells and inhibited cell proliferation, migration, and invasion in vitro. At the same time, down-regulating OSTN-AS1inhibited tumor growth in vivo. Down-regulating miR-330 promoted cell cycle progression, proliferation, migration and invasion of PC-3M cells in vitro. At the same time, down-regulating miR-330 promoted tumor growth in vivo. OSTN-AS1 negatively regulated miR-330 expressionand miR-330 negatively regulated MMP-2 expression. The inhibitory effects of down-regulating OSTN-AS1 on the cell cycle, proliferation, migration and invasion of PC-3M cells in vitro and tumor growth in vivo could be reversed by down-regulating miR-330. Conclusions OSTN-AS1 may promote the development of prostate cancer by regulating the miR-330 / MMP-2 axis, which may a molecular target for prostate cancer treatment.