Abstract: A telescopic sight includes a zoom mechanism with which an angle of adjustment of sighting can be enlarged, such that sighting precision of the telescopic sight can be stably maintained, and with which zooming can be performed with a light touch. The telescopic sight includes a zoom ring, an annular gear, a circumferential gear, an intermediate gear and a transmission mechanism. The zoom ring is turnably provided at an outer periphery of a lens barrel of a telescopic sight. The annular gear is provided at an inner periphery face of the zoom ring. The circumferential gear is rotatably provided, concentrically with the annular gear, at an inner periphery of the lens barrel. The intermediate gear is interposed between the annular gear and the circumferential gear and transmit rotation of the annular gear to the circumferential gear.