As an active security prevention technology, intrusion detection has been used in network security for a long time. But with the development and application of Internet, network attack and intrusion are constantly changing in quantity and technology level. Based on new types and concurrent attacks, traditional intrusion detection technology has been unable to meet the requirements of existing network security. As a frontier technology of machine learning and artificial intelligence, deep learning has made great achievements in speech recognition, computer vision and big data processing, and has also provided a new idea for solving the current intrusion detection problem. This paper studies the traditional intrusion detection technology based on learning method combined with the depth and the depth of the belief network, proposes an intrusion detection technology based on deep belief networks, according to the characteristics of intrusion detection data of over sampling and non [0, 1] interval of data normalization, updates the parameters in the deep belief network in the process of using variable number of the gradient descent algorithm to speed up the learning rate, the parameters of the update process, and in each batch of the training data, join the discrimination on the labels, and improve the accuracy. Experiments show that the accuracy of intrusion detection can be improved greatly by using the method proposed in this paper.