In nature, the vertical and horizontal deformation components happen simultaneously for most geohazards, which sometimes bring disasters to human beings. As an advanced radar interferometry technique, InSAR (Interferometric Synthetic Aperture Radar) can efficiently obtain ground deformation information at a global scale, but it can only obtain the deformation along radar LOS (line of sight) direction. To extract vertical and horizontal deformation components, the existing methods need at least three-track InSAR LOS measurements or azimuth measurements. However, it is generally unlikely to acquire a three-track SAR dataset covering the same region during the same time range. Herein, through mathematical deduction, we find out that both vertical and horizontal deformation components can be extracted just from two-track InSAR LOS measurements. and the analytical expressions are presented. Furthermore, the proposed method is validated by experiments. It is the first time that both vertical and horizontal deformation components have been extracted just from two-track InSAR LOS measurements without using any other measurements. Hence, it can greatly enhance the three-dimensional information acquisition ability of radar interferometry.