The temperature sensor includes a thermo-sensitive element, first and second electrode wires electrically connected to the thermo-sensitive element, first and second signal wires partially overlapped with and connected to the first and second electrode wires, respectively. The first and second electrode wires are made of a first metal material consisting primarily of Pt. The first and second signal wires are made of a second metal material containing Al and having a linear thermal expansion coefficient larger than that of the first metal material. Each of an overlap portion of the first electrode wire and the first signal wire and an overlap portion of the second electrode wire and the second signal wire includes a junction part formed by melting and thereafter coagulating the first or second electrode wire and the first or second signal wire. The junction part includes an oxidation film containing Al formed on a surface thereof.