The invention discloses a multi-functional underground dinting machine. The head part of a digging arm of the multi-functional underground dinting machine is connected with an operating head, while the tail part is provided with a support (2), a revolving device is arranged between the digging arm and a worktable, one end of a small arm (4) is rotationally connected with the operating head, whilethe other end is connected with a movable arm (5), a movable arm oil cylinder (6) is arranged above the small arm (4) and is communicated with an oil inlet pipe (10) and an oil return pipe (11) through a connecting pipe I(8) and an oil channel control valve (9) of an operating device, one end of a large arm (3) is rotationally connected with the movable arm (5), while the other end is rotationally connected with the revolving device, a large arm oil cylinder I(14) and a large arm oil cylinder II(15) are arranged above the large arm (3), and the large arm oil cylinder I(14) is communicated with the oil inlet pipe (10) and the oil return pipe (11) sequentially through a connecting pipe II(16), the large arm oil cylinder II(15) and the oil channel control valve (9) of the operating device.