Abstract: It is an important technical means to accurately evaluate the performance of laser system by measuring the spatio-temporal distribution of laser power density emitted to the far field and obtaining the key index parameters such as total power on the target, beam quality, power in the bucket and power-time curve. A method for measuring the spatio-temporal distribution of near infrared pulse laser power density based on photodetector array is introduced. The detector array can be used to measure laser spot parameters in the wavelength range of 900 nm to 1700 nm with dynamic range more than 2000 times. The detector array has the characteristics of good unit consistency and high measurement accuracy, large measurement area, and can meets the needs of pulse and continuous laser parameter measurement. The experimental results for performance of the detector array indicate that the deviation between the measured value and the laser output power is less than 5%, and the measurement results of laser spot distribution are accurate and reliable. The detector array has been successfully applied in the parameter test of several laser system, can be used as an effective technical scheme for the measurement of pulse and continuous laser spot parameters in response band.