An object of the present invention is to provide a hot melt adhesive being environmentally-friendly, having excellent adhesion property to various substrates such as paper substrate and polyolefin substrate, as well having excellent thermal stability. The present invention relates to a hot melt adhesive comprising: (A) a polar functional group-modified polymer, (B) an aliphatic polyester-based resin, (C) an olefin-based polymer, and (D) a tackifier resin.