Previously, the authors reported that dystrophin was observed under the rod cell membranes in rat retinas. However, it was not determined whether dystrophin is located in cone cells. In the current study, the authors clarify dystrophin localization in cone cells of mouse retinas.Immunoblotting, confocal laser scanning microscopy, and immunoelectron microscopy were used to investigate retinal dystrophin with a monoclonal antibody raised against the human dystrophin C-terminus.Immunoblotting analysis showed some immunoreactive bands from retinal extracts. Confocal images indicated two different immunostaining patterns: One was a tiny dot, and the other was a larger, aggregated dot. Immunoelectron microscopy revealed that retinal dystrophin was localized in cone cells as well as in rod cells.Retinal dystrophin is a common component of cone and rod cells and probably is related to the physiological function of photoreceptor cells.