This portable multi-gas detector is a personal protective pump-style gas detection device that can continuously monitor the concentration of various gases. The color TFT display screen shows the concentration of the detected gas and other information. During gas concentration detection, it alerts when the current gas concentration exceeds the set alarm point through a high-decibel buzzer, warning lights, and vibration. Additionally, this alarm device can be equipped with a wireless module to achieve remote data transmission and personnel positioning functions.