The invention discloses an analog acquisition channel voting method comprising the following steps: transmitting analog data output by a sensor through a first channel and a second channel in an acquisition mode; digitally converting the analog data of the first channel to obtain a first acquisition result; digitally converting the analog data of the second channel to obtain a second acquisition result; switching the first channel and the second channel from the acquisition mode to a diagnosis mode; injecting first test data into the first channel to get a first test result; injecting second test data into the second channel to get a second test result; and outputting a voting result according to the comparison between the first acquisition result and the second acquisition result and the comparison between the first test result and the second test result. According to the method, the output state of the two channels is diagnosed comprehensively based on the acquisition mode and the diagnosis mode, and the reliability of the system is increased.