The impact wear behavior of Ti-6Al-4V alloy treated with laser shock peening (LSP) and without treatment were investigated under sand environment using an independently developed impact wear tester. The dynamic response, interface response, and wear mechanism under different impact kinetic energies and during wear evolution were analyzed. ANOVA analysis results show that LSP has no significant effect on mechanical properties and wear resistance of Ti-6Al-4V alloys under the same test conditions. When the impact kinetic energy was relatively low or number of the impact cycles was relatively small, the worn surface was significantly higher than the original surface. When the impact kinetic energy was relatively high or the number of impact cycles was relatively large, the center of wear scars was a pit, and the edge of wear scars was higher than the original surface. Experimental results also showed that the absorbed energy was closely related to the wear of the material during the impact-abrasive wear. The greater the loss of material was, the more energy was absorbed. The impact wear mechanism under the sand condition was mainly plowing, micro-cutting, extrusion spalling, and press-in particle on the surface of the specimens.