In the process of disease diagnosis and treatment, there exists nonlinear relationship in many aspects such as the detection and analysis of symptoms. Since it is obviously efficient using artificial neural network (ANN) to solve nonlinear problems, the applications of ANN are of enormous significance. Recently, thanks to the progress on the developing application of artificial network, this technique has been widely used in fields such as diagnosis, prognosis, medical image processing and clinical decision analysis. ANN has been used as a method for early clinical diagnosis to diseases such tumor. It has also been widely applied to the image data recognition and diagnosis in medical imaging processing, the disease development and survival time prediction in prognosis, and the individualized diagnosis and treatment in clinical decision analysis.