In order to meet the requirement of data acquisition in the field of general middle and long distance industrial site，based on the Modbus communication protocol, the light intensity, temperature and humidity data collector is designed. In terms of hardware, STM32 as the main controller, using BH1750 and DHT11 to collect light information and temperature、humidity. In terms of software, reading illuminance based on the I2C protocol, and reading temperature and humidity by the singlewire bus protocol, realizing the communication with the host computer based on the RTU working mode of Modbus protocol. The system test shows that the data collector is stable and the communication between the host computer and the host computer is accurate and reliable, and the multichannel data acquisition device has been successfully applied to a section of highway tunnel lighting system in Guangxi.