We present the results of experimental examinations of the interaction of laser light with the surfaces of cast test bars. From the scientific literature, it is known that the unique properties of laser radiation result in the grained structure (called speckles) of the angular distribution for the intensity of light reflected from rough surfaces. The features of these speckles depend on the characteristics of the rough surfaces. The measuring circuit of the experimental set-up consisted of a CCD camera and a microcomputer. Computer analysis of the speckle images (or angular distributions) recorded with the camera reveal the existence of the dependencies between the parameters of surface roughness (i.e., the mean square deviation of the profile o) and some features of these images (the mean area S under the curve of light intensity for one line of the image or its contrast C). The examined samples of the castings have the values of the profile roughness height Rz from the range 10 to 160 ?m.