PURPOSE: To provide an efficient mixed-flow processing line capable of effectively dealing with automobile bodies without overstraining, by selecting prescribed pallets appropriate to the automobile bodies, from a pallet collect/distribute section, and by causing the selected pallets to flow together to a processing section.

CONSTITUTION: An automobile body processing line comprises pallets 100, a pallet collect/distribute section, a body processing section 300, a body collect/distribute section 400, a body convey-out section 500, a pallet retrieving section 600, and a line control section 700. Each pallet 100 is provided with wheels on the bottom or sides of the base and with a body-securing jig on the top of the base. The many pallets 100 are caused to stand by at the pallet collect/distribute section, so that the prescribed pallets appropriate to various kinds of automobile bodies are selected from the collect/distribute section and moved together to the processing section 300. The automobile bodies are thus dealt with smoothly and efficiently.