The invention, which belongs to the technical field of the computer vision, especially to the visual mapping technology, provides an enhancement coding method for a visual mapping target value. An image is collected and feature extraction is carried out, a corresponding target value is recorded; enhancement coding is carried out on the target value, wherein each coded bit is a 0/1 binary variable; a mapping relation between an original input image feature and binary coding is established; all input images are mapped to the binary coding based on the mapping relation; and then a mapping relation between binary coding and the target value is established by using a random forest method. For a new test picture, image feature is extracted; binary coding is estimated by using the learned model; and the binary coding is regressed to the target value. Under the circumstance that the samples are sparse and are not distributed uniformly, the sample identification rate as well as the identification precision can be improved.