Abstract: A model based on the open-circuit voltage formula of the PV-type detector, which is derived from the driftdiffusion model under the steady-condition approximation, is used to calculate the responses of PV-type HgCdTe detector under laser irradiation, in which the temperature change of detector is taken in to account. The calculation results agree well with the experiment results under weak laser irradiation; when the laser intensity is higher, the calculation results show notable deviation from the experiment results, in which the output of detector decrease rapidly when the laser begins to irradiate and increase rapidly when the laser stops to irradiate. The results suggest that when the laser intensity is higher, the hot carrier effects can’t be negligible and the model used here is n