【Objective】To develop a low-cost and simple operational system based on a smartphone for measuring the transmission of LoRa wireless undergroud data.【Method】The measurement system consisted of a smartphone with test App installed and its matching underground test nodes. Scene measurements were carried out with this system. The factors affecting the LoRa wireless data transmission in soil were determined, and the corresponding data transmission methods were discussed.【Result】The test results showed that the system was reliable and easy to operate, and LoRa low-power wide-area network technology could meet the data transmission requirements of wireless underground sensor networks in soil.【Conclusion】The system is expected to provide the appropriate testing method for the engineering application of LoRa wireless underground sensor networks in the future.