The utility model discloses an automatic drill rod washing device which comprises a cylindrical body (1). A sprayer (2) is arranged on the wall of the body (1), the water outlet end of the sprayer (2) faces the interior of the body (1), and the water inlet end of the sprayer (2) is connected to a water pump through a water inlet pipe (4). When the automatic drill rod washing device is used, the automatic drill rod washing device is arranged on a mouse hole, the water inlet pipe is connected to the water pump to pump seawater, the seawater is sprayed out of the sprayer, automatic drill rod washing can be achieved, and therefore the operation time of a driller is saved, and operation efficiency is improved.