The invention discloses a switching value signal processing method. An analog output signal of an optical coupler in a switching value signal processing device is connected to one path of Analog to Digital Converter ADC input end connected with a central processing unit CPU; actions corresponding to different direct current rated voltages input by the optical coupler and a return threshold value are pre-stored in an nonvolatile memory; and the CPU performs analog sampling on an output signal of the optical coupler, and the obtained sampling value is compared with the preset rated voltage action and the return threshold value input by the optical coupler in the nonvolatile memory so as to obtain the actual state of the switching value, namely the switching value is 1 or 0. The analog output signal of the optical coupler and an output signal of a temperature measuring chip for measuring the working temperature of the device cabinet are respectively connected to ADC input pins of the CPU; and the actions of different direct current rated voltage and the return threshold value are pre-stored in the nonvolatile memory E2PROM, and the obtained sampling value is compared with the regulated preset action and the return threshold value of the E2PROM, and the actual switching state is obtained.