Aiming at the shortcomings of small measurement range,low precision,wiring inconvenience of traditional mashgas detection instruments,a ZigBee mashgas detector based on Modbus Protocol was designed. This paper used AVR Atmega series microcontroller 169PA as the core controller, and used intelligent non-dispersive infrared mashgas sensor to form detection circuit,and used ZigBee remote transmission to communicate with the host computer to share information,multipoint measurement was realized by Modbus communication protocol. The conclusion proves that the design improves the measurement range of mashgas concentration and reduces waste and inconvenience brought by laying line,the results can form more large areas of detection,and has a high application value.