多层前向反馈式神经网络是目前应用比较广泛的人工神经网络，其中BP(Back Propagation network，简称BP网络)学习算法是最著名的多层前向反馈式神经网络训练算法之一。该算法在图像处理和图像识别领域已经取得令人瞩目的成就，其主要思想是利用已知确定结果的样本模式对网络进行训练，然后利用训练好的网络进行图像的处理或识别。本文将讨论用MATLAB实现BP神经网络对人脸角度的分析。-Multilayer feedforward neural network feedback is used widely in artificial neural networks, which BP (Back Propagation network, referred to as the BP network) learning algorithm is one of the feedback neural network training algorithm of the most famous multi-front. The algorithm in the field of image processing and image recognition has made remarkable achievements, the main idea is to use the known samples to determine the results of network training mode, and then use the trained network for image processing or recognition. This article will discuss the human face angle analysis using MATLAB BP neural network.