The network system of seismic mobile field observation has the characteristics of no public network, strong mobility, wide range, high density, and complex environment. To realize the low-cost, efficient transmission, and rapid deployment of array networking in seismic field monitoring, the LoRa network was taken as the main communication network in this paper. Combined with the wireless network technology of Wifi and ZigBee, a portable wireless compo-site communication gateway with low power and fast networking was designed and implemented. The experimental test results show that the gateway can achieve the highest air transmission rate of 21 kbps within 2 km under Lora network, and it is suitable for efficient transmission and rapid deployment of seismic field monitoring.