Disclosed is a stable-control main transformer tripping discriminating method of a large wind power integration substation. The method achieves main transformer tripping discrimination through electrical capacity and tripping position relay contacts and comprises collecting three-phase voltage and current of a main transformer and calculating active power in real time; monitoring the state of the main transformer tripping position contacts; automatically identifying the operating state of the main transformer, when abnormality alarm of the main transformer occurs or the main transformer is determined as shutdown, immediately blocking a main transformer tripping discriminating logic, otherwise, monitoring the displacement information of a TWJ (tripping position relay), performing main transformer starting discrimination, and after the main transformer is started, opening the main transformer tripping discriminating logic; during the opening process of the main transformer tripping discriminating logic, if the current active power of the main transformer is smaller than a set value and meanwhile two or more phases of TWJ signals are detected and after determination within a set delay is performed, determining main transformer tripping. The stable-control main transformer tripping discriminating method of the large wind power integration substation can well solve the influence of dynamic actions such as low-voltage ride-through and power recovery of a power grid on the main transformer tripping discrimination after large wind power is integrated, and can accurately avoid main transformer tripping mis-discrimination due to low current, active fluctuations and the like of the main transformer.