To provide a wiring structure of a loading deck elevating device which can prevent disconnection of electric wiring.

An electrical component such as a main switch of the deck elevating device fixed to a car body 101 and an electrical device such as a motor M included on the movable side of the deck elevating device and slid with a deck 29 are connected with an electrical wire 52 including a power line and a signal line. By a guide member 52, movement of the electrical wire is guided with sequential incurvating according to the sliding movement of the electrical device.