A urethral catheter. A cavity is formed at the head end of the urethral catheter, and an internal span of the cavity is greater than that of an opening. A check device (2) located at the front end of a guide core (5) is received in the cavity, and the check device (2) is a guide core (5) that can be retracted into a guide core catheter (4) and can move within the guide core catheter (4). The guide core (5) can expand outward after moving out of the guide core catheter (4). The span of the top of the expanded guide core (5) is greater than the outer diameter of the opening of the cavity at the head end of the urethral catheter. The urethral catheter eliminates a guide extension inserted inside the urethral catheter, and avoids any structural parts provided in the front end of the urethral catheter, and no accessory device is provided at the inner side of the catheter wall of the conventional urethral catheter, so that the internal urination cross-sectional area of the urethral catheter is the same as the area of the inner holes of the urethral catheter, thereby greatly increasing the urine output of the urethral catheter and greatly reducing the injection resistance of a lubricant.