The invention discloses a method and device for multi-point synchronous monitoring of carbon dioxide flux of soil in a vadose zone. Gas production columns are sequentially connected to a multi-channelcarbon dioxide infrared monitoring device through a multi-channel valve, gas production pumps are arranged on the channels, the multi-channel valve and the gas production pumps are connected to a valve-pump action controller, the carbon dioxide infrared monitoring device is connected to a workstation through a data transmission module, the data transmission module is connected to a surface meteorological condition recording module and a soil temperature and moisture content recording module correspondingly, and the soil temperature and moisture content recording module is connected to the gasproduction columns to monitor the soil environmental conditions where the gas production columns are located. The gas production pumps, the valve-pump action controller, the surface meteorological condition recording module, the soil temperature and moisture content recording module, the carbon dioxide infrared monitoring device, the data transmission module and the workstation are connected to asolar cell module. The multi-point synchronous monitoring of the carbon dioxide flux of the soil in the vadose zone can be automatically and accurately realized.