The utility model discloses a power source connecting structure of a well site loader. The system comprises loading equipment arranged on a loading machine, the loading equipment comprises a shell andfurther comprises a first mounting plate attached to the surface of the outer side of the shell, the top end of the first mounting plate is fixedly connected with a second mounting plate penetratingthrough the shell, the bottom end of the first mounting plate is fixedly connected with a third mounting plate penetrating through the shell, and the second mounting plate and the third mounting plateare connected on the inner side of the shell through bolts. A bearing plate is fixedly connected to the surface of the side, deviating from the direction where the shell is located, of the first mounting plate, a power source is arranged on the bearing plate, a baffle is fixedly connected to the bearing plate, and the side face of the baffle is perpendicular to the upper surface of the bearing plate. The utility model aims to provide the power source connecting structure of the well site loader, so as to solve the problem of complex wiring of a high-pressure pipeline caused by inconvenient movement of a power source in the prior art, and realize the purpose of realizing flexible movement of the power source in a well site by utilizing the loader.