The invention relates to a switch cabinet pressure relief device and a switch cabinet. The switch cabinet comprises a cabinet body and a switch cabinet pressure relief device disposed at the top of the cabinet body; the switch cabinet pressure relief device comprises a device frame having a pressure relief passage, the top surface of the device frame is provided with a pressure relief cover; an arc extinguishing structure is arranged in the pressure relief passage; the arc extinguishing structure comprises baffles layered along the axis of the pressure relief passage, the baffles are arrangedat intervals, and the adjacent two baffles are staggered in a direction perpendicular to the axis of the pressure relief passage and has overlapping portions along the axis of the pressure relief passage. The baffles layered along the axis of the pressure relief passage are arranged in the pressure relief passage, the arc is sprayed onto the baffle before being ejected outward along the pressure relief passage, and the baffle slows down the force of the arc to be ejected outward. A part of the arc is directly extinguished in the pressure relief device, and some of the arc may still be ejected,but the ejection force is greatly weakened, the surrounding objects will not be damaged, and the personal safety can be ensured, and safety risks due to the rapid flying out of the arc can be avoided.