An exothermic resistor for use in a hot wire air flow meter, having a wire (2) in the form of a coil made of a metal, a pair of lead wires (3) connected to connections (21) formed at the opposite ends of the coil, and a support member (4) which integrally supports the connection as well as the coil located between the connections. An example of the support member is in the form of a tubular cylinder closed at its both ends. The support member is formed from glass only or formed of a layer of a glass-ceramic-composite material. The hot wire air flow meter is designed to be easely mass-produced and to have improved transient response characteristics with respect to abrupt changes in the air flow rate.