The invention discloses a voltage flicker restraint implementation method for a static var compensator. The method includes the following steps that a busbar voltage and a load current are collected, and the busbar voltage frequency and phase change can be synchronously tracked in real time; on the basis of sequence component synchronous transformation, the load current is decomposed into a quadrature axis component and a direct axis component, and then the positive sequence quadrature axis component, the positive sequence direct axis component, the negative sequence quadrature axis component and the negative sequence direct axis component are subjected to lowpass filtering; the low pass filter coefficients of all the parts are optimally designed, and the filtered components are overlapped to form voltage flicker restraint admittance; the voltage flicker restraint admittance and closed-loop control admittance are added to obtain the total admittance of the reactive compensation system, afterwards, the total admittance is converted into a trigger pulse to be applied to a thyristor gate pole, and accordingly the efficient voltage flicker restraint function and the rapid reactive compensation function of the static var compensator are achieved. When a power grid is under serious distortion conditions such as harmonic, imbalance and frequency change, voltage flicker restraint can be achieved rapidly and accurately through the method, and a high voltage flicker improvement rate is achieved.