Highly dense, negative temperature coefficient (NTC) thermistor thick films of NiMn2O4 were fabricated on glass substrate by aerosol deposition at room temperature. The nanocrystalline films thus obtained showed superior NTC figure characteristics with a B constant of over 3900 K without heat treatment. With increasing annealing temperature, the film resistivity was gradually decreased due to crystallization and grain growth, but the B constant was maintained over 3500 K.