With regard to its geographical position, role and significance,North-Western Croatia represents the key area of the Republic of Croatia. It is the area of a long-lasting continuity of population and a great, although regionally differentiated, agrarian density. A long and intensive pressure on the environment is one of the most important factors which have influenced the ecological soil depth. Because of the presumed influence of the quantitative geomorphological features (average height, relative height, slope length, length and relative height index, inclination, surface regularity, expositions) and lithology features (rock strength coefficient)on the volume and intensity of slope processes, a multiple regression analysis has been carried out for the dependent variable of ecological depth and the quoted variables as independent assessors. [ABSTRACT FROM AUTHOR]