The portable composite gas analyzer can be used in: accurate detection and analysis of a variety of gas concentration and measurement of environmental temperature and humidity. adopted 3.5-inch high-definition color screen for real-time display, adopted the gas sensors of internationally well-known brands, and the main detection principles include: electrochemical, infrared, catalytic combustion, thermal conductivity, PID photoionization, and so on. Adopted Swiss high-precision capacitive digital temperature and humidity sensors. Advanced electric circuit design, mature kernel algorithm processing, unique external appearance design, had achieved a number of patents about the software works, external appearance, and so on. is suitable for detecting the concentrations of gases in the atmosphere environment in the pipeline or confined space; and the purity of the gas leakage and various high concentration single gases with the background gas as nitrogen gas or oxygen gas. The types for detection are more than 500 types.