The vector small perturbation theory based on Ewald Oseen extinction theorem is developed to study the laser scattering from rough surfaces. Angular spectrum of the Hermite Gaussian beam is analysed in detail and a concept of wave front cutting apart is discussed. This concept leads to the consideration that the scattering of collimated laser beams can be approximately dealt with as that of plane wave if the total incident power is used as the normalization factor, but the slender beam scattering is quite different from the plane wave. Using the obtained results, it is discussed theoretically that the concealment of 1 D rough surfaces from active detection and the scattered polarization at specular and back direction under the illumination of a ellipse polarized beam. Then distribution difference of the scattered light of vertically and horizontally polarized laser beam is introduced. The dominant conclusions are verified.