The invention discloses a single-circuit snap action temperature controller synchronization test method, which comprises synchronization test equipment and synchronization test procedures. The synchronization test method uses the synchronization test equipment, and carries out a synchronization test on a tested product according to the synchronization test procedures. The synchronization test equipment comprises a test frame, a test box, a temperature control device, PLC processor, a touch display screen, an electric signal line, an acoustic signal line and a tested product. The test method comprises an initial state, a temperature control state, a dynamic state, signal acquisition, time-differential comparison and a test result. According to the invention, the closed test box is designed, time difference analysis is carried out on circuit signals and acoustic signals, the signal reception time difference is quantified by using a time-differential device, and a synchronization characteristic of a temperature controller is accurately judged; the labor intensity is reduced, and the level of the product quality is improved; and indexes required by a customer are ensured to be reached through voluntarily adjusting the judgment time difference standard, and rising in product defective rate caused by overhigh synchronization standards is avoided at the same time.