To ensure a necessary and sufficient loading space by intercoupling a plurality of trucks as occasion demands.
This truck coupling jig intercouples two or more couplers 3 individually inserted in insertion holes 2 formed in each of two or more trucks 1 to be intercoupled. The overall length of the coupler 3 is shorter than or equal to the overall length of the insertion hole 2. This truck coupling structure is that two or more couplers 3 are mounted on a single base material. Each of the couplers 3 of the truck coupling jig 10 is individually inserted in the insertion hole 2 formed in each of the two or more tracks to be intercoupled to intercouple the trucks 1. The insertion hole 2 of the truck 1 is also served as the regulation body receiving part of the truck 1.