OBJECTIVE: To investigate the effects of tissue glutamine transaminase 2 on proliferation and directional osteogenic differentiation of rat mesenchymal stem cells derived from nasal mucosa in vitro. METHODS: Rat nasal murine mesenchymal stem cells were isolated and cultured in vitro. The effects of different concentrations of glutamine transaminase 2 on the proliferation of rat nasal mucosal mesenchymal stem cells were detected by MTT assay. The effects of glutamine transaminase 2 on the osteogenic differentiation of rat nasal mucosal mesenchymal stem cells in vitro were observed by detecting alkaline phosphatase activity, alizarin red staining and Western blotting. RESULTS: Under the microscope, the cultured cells showed a fish-like distribution. Glutaminyltransaminase 2 promoted the proliferation of nasal mucosal mesenchymal stem cells (P<0.05) and increased ALP activity (P<0.05), while enhancing mineralized nodules. The ability to form and up-regulate the expression of osteogenesis-related marker proteins COL I and OC. Conclusion: Glutamine transaminase 2 can increase the proliferation of rat mesenchymal stem cells derived from nasal mucosa and its potential for osteogenic differentiation.