The geological, physical and chemical problems dealing with the characteristics of 22 of the principal types of soils of the State of São Paulo are studied. The description of these characteristics is given quantitatively through a series of 56 diagrams, the adequate signification of which are explained. The regions of the 22 soil types are described in a abridged form as for the extent, location, geological, topographical, phytogeographical and pluviometric characteristics. Some notes referring to the rational utilization of some of these soils are given. Of the 56 diagrams presented, the 12 first mentioned are intended to compare about forty different physical and chemical characteristics of arable soil of the 22 types described. The 44 remaining graphs are physical and chemical volumetric diagrams of the 22 typical profiles, taken at the depth as far as 150 cm and divided in several genetic horizons.