A chip on film package includes a base film, a patterned circuit layer, a solder resist layer, a chip and a graphite sheet. The base film includes a first surface and a mounting region located on the first surface. The patterned circuit layer is disposed on the first surface. The solder resist layer partially covers the patterned circuit layer. The chip is disposed on the mounting region and electrically connected to the patterned circuit layer. The graphite sheet covers at least a part of the solder resist layer, wherein an outer edge of the graphite sheet is substantially aligned with an outer edge of the solder resist layer.