Disclosed is a combined rigid ureteroscope which comprises a rigid ureteroscope body and a tubular sheath outwardly fitted on a tubular part of the ureteroscope body. A starting end of the sheath is closely engaged with the tubular part of the ureteroscope body. A locking mechanism is provided at a rear end of the sheath. A locking part is provided between the tubular part of the ureteroscope body and an operation part of the ureteroscope body. The locking mechanism is cooperated with the locking part to lock or unlock the rigid ureteroscope body and the tubular sheath. In operations of examining, diagnosing and treating the ureter and the kidney by employing this invention, it saves operation procedures, shortens operation time, improves operation safety, avoids problems of difficult operation and easy damage of the flexible ureteroscope, and realizes safety, effectiveness and low cost in the clinical treatment.