Osteosarcoma is the most common primary malignant bone tumor and has a high fatality rate in children and adolescents. Recently, an increasing amount of evidence has demonstrated that lncRNAs have crucial roles in regulating biological characteristics in malignant tumors. Therefore, this research was carried out to uncover the biological function and the potential molecular mechanism of SNHG12 in osteosarcoma. In this study, we found that SNHG12 was significantly upregulated in both osteosarcoma tissues and cell lines and osteosarcoma patients with high levels of SNHG12 tended to have a poor prognosis. We evaluated the biological function of SNHG12 in 143B and U2OS cells and show that the downregulation of SNHG12 suppressed cell proliferation by blocking cell cycle progression at the GO/G1 phase and weakened cell invasion and migration abilities. Dual-luciferase reporter and RIP assays were conducted to confirm that SNHG12 functioned as a ceRNA, modulating the expression of Notch2 by sponging miR-1955p in osteosarcoma. We further demonstrate that Notch2 played a crucial role in activating the Notch signaling pathway. In conclusion, SNHG12 might serve as a valuable biomarker and prognosis factor in osteosarcoma patients. The SNHG12/miR-195-5p/Notch2-Notch signaling pathway axis might become a novel therapeutic for osteosarcoma. (C) 2017 Published by Elsevier Inc.