Scrub your grill thoroughly with steel wool. Ensure that no food waste or remnants are left in the grill to entice mice.
Cover the grill, making certain the lid is fully sealed. Wrap the grill in a tarp or grill cover. The cover should conform to the grill and not leave spaces where mice can enter.
Place mousetraps or mouse repellent around your grill.
Move your grill away from walls, drainage pipes or other locations where mice might be prevalent.