We propose a method of marker-less AR which uses line segment feature. Estimating camera poses is important part of AR system. In most of conventional marker-less AR system, feature point matching between a model and its image is required for the camera pose estimation. However, a sufficient number of correspondence points is not always detected to estimate accurate camera poses. To solve this problem, we propose the use of line segments feature that can possibly be detected even when only a few feature points can be detected. In this paper, we propose a marker-less AR system that uses line segment features for camera pose estimation. In this system, we propose a novel descriptor of the line segment feature for achieving fast computation of the camera pose estimation. We also construct a database which contains a k-d tree of line feature and 3D line segment position for finding 2D-3D line segment correspondences from input image and the database, so that we can estimate the camera pose and perform AR. We demonstrated that our proposed method can estimate the camera pose and provide robust marker-less AR in the situation where point matching method fails.