Although the similarities betw een radar imaging and diffraction tomography have been recognized, the connection betw een them is often surprising to practitioners in these fields. The main goal of this paper is to consider together tw o imaging techniques and clarify the similarities and differences that exist betw een them. First, Tw o imaging techniques are derived from Stratton-Chu formula of the inverse scattering problem, w hich allow s a clear understanding of the relationship betw een the imaging equations and the imaging targets. The targets reconstructed by radar imaging are the perfectly conducting bodies, the targets reconstructed by diffraction tomography are the dielectric bodies. Then, this derivation brings out the similarities of the solution to the unlinear imaging problem w hich are hidden by the linear approximation method, radar imaging from high frequency asymptotic approximation, diffraction tomography from w eak scattering approximation. Finally, Tw o imaging techniques are discribed as Fourier imaging, w hich is used to identify the unknow n image profile as the inverse Fourier Transform of some composite function constructed from the received data signals.