In order to study the laser damage threshold of an uncooled microbolometer, according to the construction and imaging principle of uncooled microbolometer, the temperature response mechanism of the pixel was analyzed, and the formula for calculating the temperature increment of the laser under the zero offset and single offset time was derived. A finite element analysis model of laser irradiated uncooled microbolometer was established. Simulation was carried out by loading the heat source load in combination with actual working conditions. Then the process of soft damage caused by laser was simulated. The conclusion was drawn: laser soft damage threshold approximate calculation of the pixel temperature response under zero bias conditions can be used to meet 3% accuracy. This study provides a reference for the calculation of damage threshold for laser suppression interference infrared imaging systems.