The present invention provides a process for forming a plural layer coating film which is excellent in a chipping resistance and a corrosion resistance, characterized by comprising the steps of coating a cationically electrodepositable coating material (a) on an article to be coated and curing it by heating, then coating a water based thermoplastic chipping resistant coating material (b) and controlling a solid content in the coating film to 40% by weight or more, thereafter coating a water based intermediate coating material (c) and curing both coating films of the coating material (b) and the coating material (c) by heating and then coating a top coating material (d) and curing it.