Abstract: With the rapid development of the Internet of Things，real- time，accurate，and multi-point visual monitoring of temperature has become indispensable. Based on the previously developed wide-range and high-precision nickel oxide temperature sensor，this paper proposed the appropriate size and distribution of the array-sensitive unit through the simulation of the finite element array thermal sensitivity device. In the case of the actual reaction heat source temperature，the influence on the adjacent sensitive units should be minimized. The simulation model was a four-layer structure with an array density of 4 × 4. The thickness of each layer was enlarged in the same proportion to ensure the accuracy of the simulation. The simulation optimization results of the sensitive element size showed that with the decrease of the unit area，its influence on the adjacent units gradually decreased，and the equilibrium was basically reached when the area was 8 mm × 8 mm. Before the thickness reached 1. 0 mm，the variation had a significant impact on the temperature of adjacent units. When the thickness exceeded 1. 0 mm，it had a smaller influence on the adjacent units. According to the two simulation results，the size of the sensitive layer unit in the array was determined to be 8 mm（length）× 8 mm（width）×（0. 6-1. 0）mm（height）.

Key words: temperature sensors, finite element, optimal design, thermistor, simulation study