The invention discloses a non-contact detection method for detecting the elastic parameter uniformity of a material on line. A non-contact real-time characterization method is used for the elastic parameters of a solid material, and comprises the steps of: (1) radiating pulse laser to a spatial modulator, generating two beams of coherent light after the pulse laser passes through the spatial modulator; wherein the laser source is a nanosecond or a picosecond pulse light source, the pulse light is split through the spatial modulator consisting of gratings, and the +/- level serves as a coherent light source; (2) radiating the two beams of coherent light to the surface of the tested material and generating spatial coherent interference field by utilizing an optical component lens group, forming alternately dark and bright interference fringes on the surface of the tested material, wherein the distance between the alternately dark and bright interference fringes is acquired by adjusting the lens group or the gratings; and (3) generating sound waves of which the wavelength corresponds to the distance between the interference fringes in a thin-film material after the interference fringes formed by the pulse light source are absorbed by the thin-film material, and performing non-contact detection for characterizing and analyzing the elastic parameters of the solid sample.