The invention provides a surgical assistance system with a detachable disinfection device, comprising: a support frame, a mounting arm, an anti-dropping device and a disinfection device, the support frame supports a mounting arm located in a horizontal direction, and a middle part of the mounting arm is mounted with a Disinfection device; the disinfection device includes: a disinfection bottle, a nozzle, a rotating cover, a ventilation mechanism and a mounting ring. The disinfection bottle is used to store disinfectant, the top of the disinfection bottle is provided with a ventilation hole, and a ventilation hole is installed on the disinfection bottle for opening and closing the ventilation hole. The ventilation mechanism is connected with a nozzle at the bottom of the disinfection bottle, a mounting ring around the nozzle is fixed on the disinfection bottle, the top surface of the mounting arm is recessed to form a socket for the mounting ring to be inserted, and the mounting ring cannot rotate in the socket , the installation ring is equipped with a rotating cover that surrounds the nozzle, and the rotating cover is used to open and close the nozzle; the nozzle passes through the installation arm. The surgical assistance system with a detachable sterilization device solves the problem of inconvenient detachment and installation of the sterilization bottle in the prior art.