PURPOSE: To lock a floor part rapidly to a horizontal frame by disposing a lock rod, energized in the direction of a pivot point of a floor part, on the back face of the floor part while disposing a locking member, protrusively provided with a hook, at the horizontal frame in a cage cart used for the storage and transportation of goods or the like.

CONSTITUTION: At the time of assembling a cage cart, a floor part 7 positioned almost vertically in a folded state is rotated downward around a pivot point on the left side. A lock rod c2 elastically supported on the floor part 7 is thereby brought into colliding contact with a hook c8 on a locking member c7 erected on a horizontal frame 1 provided with casters 8 at the corner parts. When the floor part 7 is further pressed downward from this state, the lock rod c2 moves toward the tip along a guide face c8' against a compression coil spring c6 and then goes over the tip of the hook c8 and comes off the hook c8. That is, the lock rod c2 is locked by the compression coil spring c6 and the locking member c7 to connect the floor part 7 to the horizontal frame 1.