Osteosarcoma (OS), a prevalent aggressive malignancy in the bone, has limited therapeutic targets and diagnostic biomarkers. In the current investigation, RT-qPCR showed that CDKN2B-AS1 was enhanced in OS samples and cells. This research was set to examine the modulation of CDKN2B-AS1 in OS. The expression of CDKN2B-AS1 and downstream molecules was analyzed by RT-qPCR method. CCK8, EdU staining along with Transwell assays were applied to evaluate cell proliferation and invasion. Those in vitro investigations specified that silencing of CDKN2B-AS1 with shRNAs obviously impeded the proliferation and invasion of MG63 cells. To authenticate the relationships between CDKN2B-AS1 and microRNA-122-5p (miR-122-5p) or cyclin G1 (CCNG1) and miR-122-5p, we next employed luciferase reporter assay. We displayed that CDKN2B-AS1 repressed miR-122-5p to restore CCNG1 expression. All in all, our findings substantiated the indispensable function of CDKN2B-AS1 in OS progression and the possible molecular mechanism.