Abstract: The structure of the present invention "a fully automatic single-person operated grease gun injection device" comprises of an exterior case body, a generating device system, a compressed grease pump, a grease scratching/collecting harrow control connecting rod, a rolling cylinder, a grease gun, etc. By means of the precedingly mentioned structures, the fully automatic grease gun injection device thus composed can provide an application operation for a single person so as to achieve the operational effect of grease injection and the upgrading of working efficiency.