A method for detecting and characterizing a moving target (13; 14) on a SAR image representing the reflectivity echoes of an area illuminated by a radar beam of a platform formed by a repetition of radar acquisitions, that comprises the following steps: - a first step of eliminating the stationary fixed echoes with high reflectivity measured on the radar image, said first step comprising the following steps: - reduction of the reflectivity of the moving echoes, consisting in retaining, for each pixel of the radar image, the minimum reflectivity for the whole set of repeated radar acquisitions, - detection of the fixed echoes by a thresholding operation, - a second step of reducing the integration time by extracting the central temporal illumination portion on the radar image, - a third step of focusing the echo of the moving target by applying a correction of the range migration and the Doppler migration of the moving target on the radar image, - a fourth step of extracting the moving target from the radar image, said fourth step comprising a thresholding operation of the pixels of the radar image, - a fifth step of calculating the position of the target and the components of the velocity vector of the target, including at least the component projected on the route of the platform, obtained according to the following relation: φ 2, C / M t = − 4 π λ × V × V cV R c × t 2 − λπ 2 R c 2 f d M + k amb × f r × k amb × f r × t 2 where: - t represents time; - λ: wavelength; - R c: the range between said platform and said target; - φ 2,C / M ( t): the residual defocusing of said target; - V cV: component of the target velocity vector along the aircraft route; - k amb: Doppler ambiguity rank of the target; - M c: apparent position of the target, that is to say the position of the ground point located at the same distance as the target; - f d M: Doppler frequency of the point M c; - f r: repetition frequency. - a first step of eliminating the stationary fixed echoes with high reflectivity measured on the radar image, said first step comprising the following steps: - reduction of the reflectivity of the moving echoes, consisting in retaining, for each pixel of the radar image, the minimum reflectivity for the whole set of repeated radar acquisitions, - detection of the fixed echoes by a thresholding operation, - a second step of reducing the integration time by extracting the central temporal illumination portion on the radar image, - reduction of the reflectivity of the moving echoes, consisting in retaining, for each pixel of the radar image, the minimum reflectivity for the whole set of repeated radar acquisitions, - detection of the fixed echoes by a thresholding operation, - a second step of reducing the integration time by extracting the central temporal illumination portion on the radar image, - a third step of focusing the echo of the moving target by applying a correction of the range migration and the Doppler migration of the moving target on the radar image, - a fourth step of extracting the moving target from the radar image, said fourth step comprising a thresholding operation of the pixels of the radar image, - a fifth step of calculating the position of the target and the components of the velocity vector of the target, including at least the component projected on the route of the platform, obtained according to the following relation: φ 2, C / M t = − 4 π λ × V × V cV R c × t 2 − λπ 2 R c 2 f d M + k amb × f r × k amb × f r × t 2 where: - t represents time; - λ: wavelength; - R c: the range between said platform and said target; - φ 2,C / M ( t): the residual defocusing of said target; - V cV: component of the target velocity vector along the aircraft route; - k amb: Doppler ambiguity rank of the target; - M c: apparent position of the target, that is to say the position of the ground point located at the same distance as the target; - f d M: Doppler frequency of the point M c; - f r: repetition frequency. - t represents time; - λ: wavelength; - R c: the range between said platform and said target; - φ 2,C / M ( t): the residual defocusing of said target; - V cV: component of the target velocity vector along the aircraft route; - k amb: Doppler ambiguity rank of the target; - M c: apparent position of the target, that is to say the position of the ground point located at the same distance as the target; - f d M: Doppler frequency of the point M c; - f r: repetition frequency.