The invention provides a luggage security inspection integrated machine with integration of nuclear alarming, chemical agent alarming, and X ray detection. The integrated machine comprises a conveyingdevice, a communication module, a central control system and a detection cabin. A chemical agent alarming device, a nuclear alarming device, and an X ray device are arranged in the detection cabin. The conveying device conveys luggage into the detection cabin; the chemical agent alarming device detects chemical agent gas dissipated from the luggage; the nuclear alarming device detects radioactivesubstances; and the X ray device detects controlled metal articles and explosives. The chemical agent alarming device, the nuclear alarming device, and the X ray device transmit luggage detection results to the communication module in real time; and the communication module sends the detection results to the central control system to carry out analysis, determination, and processing. On the basisof the modular design, the integrated machine is easy to dismount or mount and is easy to repair and is connected with the national security system, thereby guaranteeing the travel safety of people.