The breast of 160 females clinically diagnosed as having diffuse fibrocystic mastopathy and 61 females without clinical manifestations of breast diseases were echographically studied. The ultrasonographic design included measurement of the layer thickness of glandular tissue and its echodensity. In all diffuse mastopathies, including cystic one, there was over 14-mm glandular tissue thickness in all the portions of the breast or in its any quadrant, as well as glandular tissue echodensity changes which do not correspondent to the patients' age. In the control group, the thickness of a glandular layer varied with age, but it was no greater than 14 mm. Thus, the studies have demonstrated that over 14-mm glandular layer thickness and age-unspecific glandular tissue changes are the symptoms of diffuse fibrocystic mastopathy. The authors propose to include the measurement of these parameters into breast ultrasonographic methods since this allows one not only to make a more accurate diagnosis, but to clearly identify an echographic type of mastopathy.