The invention relates to a parameter optimization method for a backup power parallel reactor based on an anti-typhoon running mode of a wind power plant. The method comprises the following steps: firstly, integrally modeling for the system under the anti-typhoon running mode, wherein the system model comprises a backup power supply, a backup power parallel reactor, a backup power transformer, a direct buried cable and a plurality of multi-path wind turbine generator equivalent models; respectively calculating power loss of system elements in the models; confirming the parameter of the reactor requiring parallel connection according to the system power factor before optimization and the realized power factor after optimization. The parameter optimization method for the backup power parallel reactor based on the anti-typhoon running mode of the wind power plant, provided by the invention, is used for optimizing the oversize capacity current into lower sensitive current and is beneficial to the closing operation of the circuit breaker.