The invention discloses a high-voltage DC lightning arrester parameter design method. The method comprises the following steps: in the premise of knowing a technical performance index to be satisfiedby a lightning arrester, determining the number of the valve blocks in series connection of the lightning arrester through the preset number of the lightning arrester column according to the parameterof the valve block of the lightning arrester, and then gradually determining the maximum absorption energy, the DC reference voltage and like electrical parameters of the lightning arrester, and verifying the reasonability of the lightning arrester parameter design through the electromagnetic transient simulation, thereby forming a closed-loop of index giving-parameter designing-index verification in simulation-design parameter adjusting-index verification. Through the closed-loop iterative checking, the lightning arrester valve block model and the lightning arrester parameter satisfying theperformance index can be output, and the reasonability of the model and the parameter is further checked through electromagnetic transient simulation, thereby forming a normalized high-voltage DC lightning arrester parameter design method, the reasonable parameter of the lightning arrester can be simply and quickly determined, and the method has strong engineering actual significance for guiding the DC power transmission engineering lightning arrester parameter design.