The invention relates to a beam column joint novel diagonal member metal energy dissipation device. The device comprises a first arc steel plate and a second arc steel plate, two U-shaped steel plates and one web are connected between the first arc steel plate and the second arc steel plate, and the web is located between the two U-shaped steel plates; a first connecting steel plate is arranged at one end of the first arc steel plate; at least one arc steel rib is arranged at the outer side of the first arc steel plate, and a second connecting steel plate is arranged at one end of the second arc steel plate; at least one second arc steel rib is arranged at the outer side of the second arc steel plate; the first connecting steel plate and the second connecting steel plate are located at different ends of the energy dissipation device. According to the beam column joint novel diagonal member metal energy dissipation device, the problems are solved in the prior art that an existing energy dissipation device is complicated in structure, occupies the building using space, and is high in manufacturing cost, complicated in disassembly and assembly, and uneasy to replace.