The invention provides a method and a system for evaluating the low-voltage ride-through performance of a photovoltaic power station. The method comprises the steps of simulating a low-voltage ride-through working condition, and correcting a pre-built photovoltaic power station model based on the response performance of a type test inverter; simulating a low-voltage fault of a power grid on the basis of the corrected photovoltaic power station model, obtaining voltage and current data, and calculating a response characteristic of a grid connection point of the photovoltaic power station model;and evaluating the grid connection performance of the photovoltaic power station based on the response characteristic of the grid connection point of the photovoltaic power station model. The consistency of the performance of the photovoltaic power station and an inversion unit is realized; the modeling is simple; and the integrity and the accuracy are high. The grid connection performance of thephotovoltaic power station can be evaluated more comprehensively; the scientificity of evaluation is improved; and the cost is reduced.