The invention relates to the technical field of robots, pipeline dust treatment or coal mines, in particular to an L-shaped rotating cavity dust suction rod assembly. The L-shaped rotating cavity dustsuction rod assembly comprises a fixed pipe and a dust suction pipe. The dust suction pipe includes a first pipe section and a second pipe section which are fixedly connected to each other. The firstpipe section and the second pipe section are matched to be arranged in an inverted L shape. Two partition plates are arranged in the fixed pipe at an interval. The first pipe section penetrates through the two partition plates to be arranged in the fixed pipe in a sleeving mode. A chamber between the two partition plates forms a communication cavity. A second hoe channel is arranged on the side wall, corresponding to the communication cavity, on the fixed pipe, and a first hole channel is arranged on the side wall, corresponding to the communication cavity, on the first pipe section. The driving resistance of a swing cylinder is smaller, the L-shaped rotating cavity dust suction rod assembly is more energy-saving, a dust pumping hose does not swing in a following mode so the dust pumpinghose can be fixed, and the dust pumping hose does not interfere with other parts.