Abstract: Short-exposure laser power meters have the advantages of high measurement efficiency and low cost, and have a broad application prospect in high-power laser measurement. A short-exposure laser power meter was designed, and the temperature response characteristics of the detector under different power lasers and different laser irradiation times were experimentally studied. The experimental results show that the temperature rise data at the end of the laser for 10 s can better characterize the laser power. The nonlinear deviation of the detector response is less than 3% when the duration of the detector is less than 1 s, and the nonlinear deviation of the detector response is not more than 5.5% when the duration of the laser is less than 2 s. A three-dimensional finite element model of the detector was developed. Simulations were carried out for scenarios with heat dissipation and without heat dissipation, respectively. The results show that the influence of heat dissipation on the nonlinearity of the detector response is small, the nonlinearity of the response in a short time is mainly caused by the heat transfer process, and the main factor affecting the linearity of the detector response in a long time is the measurement of signal-to-noise ratio.