To meet the requirements for long-term monitoring of hazardous gases in environmental monitoring systems, a wireless gas sensor with a low-power operation strategy was designed. The sensor integrated detection modules of methane, carbon monoxide, and carbon dioxide concentrations, with STM32L071CBT6 as the core microprocessor for data acquisition, processing, and storage. A LoRa wireless communication module was employed to transmit monitoring data to the industrial ring network. On this basis, low-power operation strategies and energy management mechanisms were proposed, and experimental verification was conducted on the wireless gas sensor. The results show that the sensor can monitor the concentrations of methane, carbon monoxide, and carbon dioxide in real-time and accurately, and the detection errors are within the allowable error range of the sensitive components; Based on a 6 000 mA·h battery capacity, the implementation of low-power operation strategies and Autosleep power management mechanism extends the monitoring duration to 142.9 days, representing a 378% increase compared to continuous operation mode. The designed wireless gas sensor demonstrates significant application value with competitive performance indicators, providing theoretical reference and practical guidance for intelligent environmental monitoring systems and wireless sensor design.