A seat with a heating device is provided which realizes a configuration in which the arm, palms and finger tips of a user can easily be warmed when the user uses the seat with the heating device. When the user is seated in a seat with a heating device and feels cold due to it being winter, the user controls a switch to heat the seat, whereby energization of heating elements 3a, 3b, 3c is started which are connected to a power supply via electric wires. When the energization of the heating elements 3a, 3b, 3c is started, heat generated thereby is conducted to skin materials 2a, 2b, 2c and surfaces of the skin materials are warmed. When the user places his or her arm on an armrest portion 5, the arm is warmed via the skin material 2c, whereby the user can feel the sensation of comfortableness.