The invention relates to a disposable cystoscope sheath. To solve the problem of mutual cross-infection during medical inspection. The technical solution adopted is: a disposable bladder inspection mirror sheath, including a sheath tube, a sheath main body, an instrument valve, a short bridge, a water inlet valve and a water outlet valve, and it is characterized in that: said sheath tubes are provided with independent speculum cavities And the instrument channel, the front end of the speculum cavity is provided with a transparent window for sealing the speculum cavity, the front end of the instrument channel is open, the front section of the instrument channel is curved, and forms a certain angle with the front section of the speculum cavity; It is connected with the instrument channel and the main body of the sheath, and the speculum cavity is connected and communicated with the short bridge connected in the main body of the sheath; one end of the instrument valve is inserted in the main body of the sheath, and the other end of the instrument valve is equipped with a rubber cap; the main body of the sheath is provided with an inlet The water valve and the water outlet valve; the water inlet valve, the water outlet valve, the instrument channel and the main body of the sheath communicate with each other. The invention creates an integrated structure, which is simple and convenient to operate, economical, practical and safe.