The conventional preparation process of VO2 temperature sensors requires the precise control of ambient atmosphere. This is one of the difficulties in their application to integrated devices. Laser sintering proved to be useful in overcoming this difficulty. Specimens of VO2 film (1.4×1.4×0.04 mm3 in size) printed on alumina substrates changed in electrical resistance by a factor of 102 at about 68 °C with increasing temperature, after exposing them, in open air, to a 2-ms pulse beam from a ruby laser on relaxation oscillation, whose energy density was 6.5 J/cm2.