According to the infrared radiation theory,thermal radiation model of the inner surface of the cabinet is established.The radiation results from the overheating of single or multiple components in the control cabinet.And total heat flux distribution of the inner surface of the casing is obtained.Then,a two-dimension heat transfer model of the heated casing is developed.An inverse heat conduction problem is studied by the Levenberg-Marquardt method based on the infrared imaging temperature measurement on the surface of the casing.And the temperature and the position of the overheating components in the control cabinet are identified together.Finally,the effects of measurement errors on computational results are analyzed.The results show that the L-M method is very suitable to estimate the temperature and the horizontal distance of single overheating component.And it is also very suitable to estimate the temperature and the position of two overheating components together.The effect of measurement errors on the temperature estimating of the overheating component is large.