We propose a ground target recognition method based on 3D laser radar data. The method handles general 3D scattered data. It is based on the fact that manmade objects of complex shape can be decomposed to a set of rectangles. The ground target recognition method consists of four steps; 3D size and orientation estimation, target segmentation into parts of approximately rectangular shape, identification of segments that represent the targets functional/main parts and target matching with CAD models. The core in this approach is rectangle estimation. The performance of the rectangle estimation method is evaluated statistically using Monte Carlo simulations. A case study on tank recognition is shown, where 3D data from four fundamentally different types of laser radar systems are used. Although the approach is tested on rather few examples, we believe that the approach is promising.Keywords: Rectangle estimation, laser radar, automatic target recognition 1 Ground target recognition using rectangle estimation Christina Grönwall, Fredrik Gustafsson, Mille Millnert Abstract-We propose a ground target recognition method based on 3D laser radar data. The method handles general 3D scattered data. It is based on the fact that man-made objects of complex shape can be decomposed to a set of rectangles. The ground target recognition method consists of four steps; 3D size and orientation estimation, target segmentation into parts of approximately rectangular shape, identi cation of segments that represent the target's functional/main parts and target matching with CAD models.The core in this approach is rectangle estimation. The performance of the rectangle estimation method is evaluated statistically using Monte Carlo simulations. A case study on tank recognition is shown, where 3D data from four fundamentally different types of laser radar systems are used. Although the approach is tested on rather few examples, we believe that the approach is promising.