Nitrogen controlled atmosphere control method and system

The invention provides a nitrogen controlled atmosphere control method and system. The method comprises the following steps that oxygen concentration in a controlled atmosphere cabin is detected in real time, and air output of a nitrogen making machine is regulated according to the obtained first oxygen concentration detection value through detection and a corresponding relation of the preset oxygen concentration of the air outlet of the nitrogen making machine and air output. Compared with regulation on the basis of experience, regulation accuracy is enhanced, and the nitrogen making machine can be controlled to operate under the excellent working condition without multiple times of repeated regulation so that the control process is shortened.