A depth estimation algorithm from monocular infrared image based on nonlinear learning model is proposed in this paper.Firstly,some features corresponding to the depth of infrared image are extracted using stepwise regression and ICA.Secondly,based on the nonlinear SVM model with kernel function,we regress and train the depth features of infrared image using supervised learning method.During the training process,the model parameters are fixed by calculating MMSE from regression analysis of the known data.Finally,we get the depth estimation model which can estimate the depth distribution of monocular infrared image.The experimental results show that most of the depth estimated by the model is consistent with the original depth information of infrared image.