Objective　To explore the effects of axon guidance molecular EphA5 on mesostriatal projection. Methods　Immunofluorescence staining was performed to examine the expression of EphA5 in embryonic neuroepithelial stem cells of mesencephalon and the expression of Ephrin-A5 in striatum, while, RT-PCR and Western-blot techniques were performed to detect the expression of mRNA and protein of Ephrin-A5 in striatum. Furthermore, neuroepithelial stem cells were co-cultured with striatum explants of newborn rat brains for exploring targeted growth of cultured cells.  Results　A great quantity of neuroepithelial stem cells were EphA5 positive, with the high expression of Ephrin-A5 in striatum. Co-cultured mesencephalon neuroepithelial stem cells extended towards the striatum. Conclusions    This study suggests that axon guidance molecular EphA5 receptor and its ligand Ephrin-A5 promotes the axon growth of neuroepithelial stem cells toward striatum during development, and these two molecules mediate the establishment of mesostriatal projection.