A heat pipe includes a tube body and a sealing member. The tube body is made of titanium and has a sealed end and an open end at two opposite ends of the tube body. The sealing member is attached to the open end and seals the open end of the tube body. The sealing member is made of a material selected from one of copper, aluminum, stainless steel, low-carbon steel, iron, nickel, tungsten, tantalum, molybdenum, rhenium and columbium. The sealing member seals the open end.