Conclusions: The adenovirus-5 vector specifically transduced spiral ganglion cells with high efficiency, suggesting that it is a potential gene therapeutic tool for the survival of spiral ganglion cells with secondary injury. Objectives: This study aimed to find a suitable viral vector allowing efficient transduction to spiral ganglion cells. Methods: Lentivirus, adeno-associated virus-2 and adenovirus-5 constructs habouring green fluorescence protein (GFP) gene were injected into scala tympani via the round window membrane of rat. Distribution and fluorescence intensity of GFP within the cochlea were estimated using a fluorescence microscope. Results: The GFP expressions mediated by all three viral vectors were observed in multiple cell types of the cochlea. Compared with the other two viral vectors, the adenovirus-5 vector efficiently transduced cochlear spiral ganglion cells in vivo and was still present 2 weeks after viral vector injection.