Provided is a battery module in which a heat radiation effect and manufacturing efficiency are effectively improved. The battery module includes a cell assembly including at least one unit body, each unit body including at least two secondary batteries stacked in a first direction. Each unit body includes an integrated unit sheet folded to surround a top portion, a left surface, a right surface, and a bottom portion of the at least two secondary batteries, opposite ends of a top portion of the integrated unit sheet being positioned to contact each other on any one of the top portion, the left surface, the right surface, and the bottom portion of the at least two secondary batteries, and an electric insulating material coated on at least a part of a perimeter portion of the integrated unit sheet.