The invention provides a DC power transmission system filter switching strategy optimization method and device thereof. The method includes making a statistic of the information of a power system partition; checking the reasonability of the built data; making a statistic of the DC power transmission system filter parameters; selecting an alternative switching strategy from the formulated switchingstrategy; and analyzing the reasonability of the alternative scheme, and determining an optimal switching strategy. According to the technical scheme, the fluctuation amplitude of DC near-area voltage caused by unreasonable filter switching strategies is reduced, the unnecessary analysis is reduced, the calculation is simple, and the adaptability is wide.