The invention discloses an automatic rubber-coating device installed on an automatic coil winding machine, which is used for coating a rubber belt on a rubber-coating piece. The automatic rubber-coating device comprises a movably-arranged base plate, a rubber belt unwinding wheel assembly, a rubber belt guide assembly, a rubber belt winding assembly, a belt cutting assembly and a belt pressing assembly, wherein the rubber belt unwinding wheel assembly, the rubber belt guide assembly, the rubber belt winding assembly, the belt cutting assembly and the belt pressing assembly are arranged on thebase plate. The rubber belt unwinding wheel assembly is positioned at the upper part of the base plate, the rubber belt guide assembly is positioned at the middle part of the base plate, and the rubber belt winding assembly, the belt cutting assembly and the belt pressing assembly are positioned at the lower part of the base plate. The rubber belt winding assembly comprises a winding elastic piece which is used for tightly pressing the rubber-coating device during rubber coating. The belt cutting assembly comprises an ending elastic piece, and a cutter used for cutting off the rubber belt is fixedly arranged on the ending elastic piece. The automatic rubber-coating device adopts the elastic piece to tightly press the rubber belt on the rubber-coating piece for coating rubber, and the traditional roller tightly-pressing rubber coating is replaced. The automatic rubber-coating device can greatly reduce the defects existing in the traditional rubber-coating device, as follows the coated rubber is loose, the rubber is not coated, the rubber is coated obliquely and the like. The ratio of fishing products of rubber coating is increased.