The invention discloses an ablation-resistant tungsten copper alloy and application thereof. The ablation-resistant tungsten copper alloy comprises the following components in percentage by mass: 78-83 percent of tungsten, 16.6-21.75 percent of copper, 0.25-0.4 percent of nickel and 0.1-4 percent of titanium diboride. The preparation method comprises the following steps: pressing tungsten powder, nickel powder, titanium diboride powder and preloaded copper powder, presintering to form a porous tungsten skeleton; infiltrating and sintering a copper green compact into the porous tungsten skeleton, thereby obtaining the ablation-resistant tungsten copper alloy. The prepared ablation-resistant tungsten copper alloy can effectively resist arc ablation caused by overvoltage generated during lightning stroke, so that an insulator chain is prevented from being subjected to breakdown, and the aim of prolonging the service life of a lightning protection device is achieved. Moreover, the ablation-resistant tungsten copper alloy has excellent ablation resistance and can serve as a good discharge material.