The invention discloses an automatic wiping device of a gun pipe. The automatic wiping device comprises a self-adaptive reciprocate wiping head, a six-wheel full-driving self-adaptive walking mechanism, a self-adaptive rotating steel brush head and a self-adaptive universal wheel guide mechanism; the six-wheel full-driving self-adaptive walking mechanism comprises three groups of rotatable wheel feet of which two are formed to be one group; a dual-hook spring is arranged between every group of rotatable wheel feet; the reciprocate wiping head comprises a driving motor, a worm structure, a crank and rocker mechanism, wiping blocks, a wiping block turn table and a driving part; the wiping blocks are evenly distributed at four sides of a round disk of the wiping block turn table; an outer periphery of the self-adaptive rotating steel brush head is provided with several steel brushes; the self-adaptive universal wheel guide mechanism is arranged at inside of the self-adaptive rotating steel brush head. By adopting the full-automatic control method, the existing manual cleaning, and semi-automatic cleaning, and other methods with low efficiency are replaced; and thereby, the efficiency of wiping the gun pipe is improved.