Object detection is one of the most important research topics in autonomous vehicles. The detection systems of autonomous vehicles nowadays are mostly image-based ones which detect target objects in the images. Although image-based detectors can provide a rather accurate 2D position of the object in the image, it is necessary to get the accurate 3D position of the object for an autonomous vehicle since it operates in the real 3D world. The relative position of the objects will heavily influence the vehicle control strategy. This thesis work aims to find out a solution for the 3D object detection by combining the Lidar point cloud and camera images, considering that these are two of the most commonly used perception sensors of autonomous vehicles. Lidar performs much better than the camera in 3D object detection since it rebuilds the surface of the surroundings by the point cloud. What’s more, combing Lidar with the camera provides the system redundancy in case of a single sensor failure. Due to the development of Neural Network (NN), past researches achieved great success in detecting objects in the images. Similarly, by applying the deep learning algorithms to parsing the point cloud, the proposed 3D object detection system obtains a competitive result in the KITTI 3D object detection benchmark.