The invention discloses a method and system for preventing error drive of an ATWT (Anticipated Transients without Trip) equipment cabinet, wherein the method comprises the following steps of: collecting a main feedwater flow signal and a nuclear instrument signal; collecting a power loss signal of a reactor protection equipment cabinet; outputting a first signal after the power loss signal and the main feedwater flow signal are subjected to a first logic AND treatment; and outputting a second signal after the first signal and the nuclear instrument signal are subjected to a second logic AND treatment, wherein the second signal is used for determining whether ATMT happens or not. Through the collection of the power loss signal of the reactor protection equipment cabinet and the corresponding logic treatment of the signals, the error protection of the ATWT is effectively inhibited.