A crossbar assembly and a trip assembly comprising same are disclosed. The crossbar assembly according to an embodiment of the present disclosure comprises a crossbar and an instant bar. The crossbar and the instant bar can be rotatably coupled so as to be rotatable around the same rotary shaft. Therefore, the space required for rotation can be reduced to be less than when the crossbar and the instant bar are individually rotated. In addition, the crossbar can move in a longitudinal direction when coupled to the instant bar. Therefore, a metallic bar for movement of the crossbar is unnecessary. Therefore, interference between different-phase currents flowing through the trip assembly can be minimized.