AIM: To investigate the effect of the overexpression of C-X-C chemokine receptor type 4 (CXCR4) on homing of mesenchymal stem cells (MSCs) in vitro and therapeutic effects of diabetic retinopathy (DR) in vivo. METHODS: MSCs were infected by lentivirus constructed with CXCR4. The expression of CXCR4 was examined by immunofluorescence, Western blot, and quantitative polymerase chain reaction. CXCR4-overexpressing MSCs were cultured in vitro to evaluate their chemotaxis, migration, and apoptotic activities. CXCR4-overexpressing MSCs were intravitreally injected to observe and compare their effects in a mouse model of DR. The histological structure of DR in rats was inspected by hematoxylin and eosin staining. The expression of rhodopsin, neuron-specific enolase (NSE), and inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α was examined by Western blot and immunohistochemical analyses. RESULTS: The transduction of MSCs by lentivirus was effective, and the transduced MSCs had high expression levels of CXCR4 gene and protein. Improved migration activities were observed in CXCR4-overexpressing MSCs. Further, reduced retinal damage, upregulation of rhodopsin and NSE protein, and downregulation of inflammatory cytokines IL-6 and TNF-α were observed in CXCR4-overexpressing MSCs in vivo. CONCLUSION: The homing of MSCs can be enhanced by upregulating CXCR4 levels, possibly improving histological structures of DR. CXCR4-overexpressing MSCs can be a novel strategy for treating DR.