Hydrochloric acid doped thin film of poly-o-methyl aniline (POMANI)-Mn3O4 nanocomposites have been fabricated on glass substrate. The nanocomposite films showed RT-NTC characteristics in the temperature range of 35-185 degrees C with repeatability in the temperature range of 75-185 degrees C. The cut off temperature of the thermistor fabricated from the nanocomposite material was found to be between 165 and 170 degrees C. Synthesised nanocomposite material has been characterized using FT-IR, XRD, TEM for structure, morphology and TGA/DTC for thermal stability. Thermistor constant (beta) observed from RT characteristics are in the range of 7363 K-10,188 K and activation energy (Delta E) was calculated which was in the range 0.634 eV-0.878 eV. Further linearization of thin film based NTC thermistors was carried out using an low cost analog circuit by adding parallel (R-P), series resistance (R-S) and operational amplifier (OP-AMP). It has been observed that these thin film based temperature sensors have repeatable temperature sensing behavior on linearization with high sensitivity and low power dissipation (P-diss)2015 (C) Elsevier B.V. All rights reserved.