A constant-pressure variable-flow insufflator, comprising a housing , wherein an insufflator gas inlet , an insufflator gas outlet , a smoke removal gas inlet , and a smoke removal gas outlet are respectively provided on an outer side of the housing ; the insufflator gas inlet is connected to an external gas source through a pressure relief valve A ; the insufflator gas outlet is connectable to an abdominal cavity of a patient through a filter A ; the smoke removal gas inlet is connectable to the abdominal cavity of the patient through a filter B ; the smoke removal gas outlet is communicated with a vacuum extractor ; a control module , a pneumatic module , a temperature detection module , a safety module , a temperature control module , and a smoke removal module are arranged in the housing ; the control module is in signal connection with each of the pneumatic module , the temperature detection module , the safety module , the temperature control module , and the smoke removal module for driving a system and performing digital signal processing on collected data; the pneumatic module is configured for controlling pressure, temperature, and flow of gas delivered by the external gas source; the temperature detection module is configured for detecting the temperature of the gas delivered by the external gas source; the safety module is configured for detecting temperature of the control module and the pneumatic module; and the temperature control module is configured for reducing noise while cooling an interior of a chassis; and the smoke removal module is configured for exhausting smoke generated in the abdominal cavity of the patient, wherein the pneumatic module comprises a filter C , a pressure sensor A , a heating pressure relief valve , a safety valve , a pressure sensor B , a proportional valve module , a flow sensor , and a switching valve module ; one end of the filter C is connected to the insufflator gas inlet through a pipeline, and another end of the filter C is connected to the heating pressure relief valve through the pipeline; another end of the heating pressure relief valve is connected to one end of the safety valve through the pipeline; another end of the safety valve is connected to the proportional valve module through the pipeline; one end of the proportional valve module is connected to one end of the flow sensor through the pipeline; another end of the flow sensor is connected to one end of the switching valve module through the pipeline; another end of the switching valve module is connected to the insufflator gas outlet ; the flow sensor is in signal connection with the control module ; the pressure sensor A is arranged on the pipeline between the filter C and the heating pressure relief valve ; the pressure sensor A is in signal connection with the control module ; the pressure sensor B is arranged on the pipeline between the safety valve and the proportional valve module ; and the pressure sensor B is in signal connection with the control module ; and wherein the safety module comprises a temperature sensor C and a temperature sensor D ; the temperature sensor C is arranged on an outer side of the heating pressure relief valve ; the temperature sensor C is in signal connection with the control module for detecting a temperature of the heating pressure relief valve ; and the temperature sensor D is mounted on the control module , and is in direct signal connection with the control module for detecting a temperature of the control module . <EOS>