The high-power CO2 laser disturbance to Long-wave Infrared (LWIR) HgCdTe detectors is investigated theoretically and experimentally in this paper.Based on the practical parameters of experiments, a theoretical model of temperature-rise is adopted to calculate the variation of temperature with the time and the power of laser irradiation on a detectors.Then, the high-power laser damage mechanism to the LWIR detector is discussed, and obtained results are compared with the experimental results from that a CO2 laser irradiates the detector on the distance of 15 km.The experimental results show that the power density of the CW CO2 laser with the power of 2.5 kW can achieve 0.16 W/cm2 after attenuation for 15 km distance.Therefore, the power density of the target after focusing by a lens can be 140 W/cm2 by calculation.Furthermore, when the power density of the target is 20.5 W/cm2, the detector can be jammed; when it achieves 110 W/cm2, the detector can be damaged and the detector temperature is high enough for Hg deposition.This experimental phenomenon well agrees with the results predicted by the theoretical calculation.The conclusions can provide references for the laser defense of detectors and laser jamming satellite-based detectors.