A holographic method with numerical reconstruction for obtaining an image of a three-dimensional object, employs a digitalized hologram of an object or of a portion thereof, and includes starting from the digitalized hologram, extracting a phase image of the object corresponding to a matrix MD of distance values, selecting a subassembly SD of the distance value assembly present in matrix MD, subassembly SD containing distance values d k, extracting from matrix MD an iso-level assembly IQd k of corresponding bidimensional coordinate of the object; reconstructing, for each distance value d k, a bidimensional matrix IMd k of intensity values relevant to the object; extracting, from each bidimensional matrix IMd k, a bidimensional IFd k of intensity values; and starting from the intensity values, reconstructing the three-dimensional intensity image of the object.