With the present paper the authors had in mind to work out a photogeological survey in the southern part of the State of São Paulo in order to obtain a basic map for future detailed work. For this purpose aerial photographs and mosaics of the Insttiuto Agronômico were used, ata 1:25.000 scale. The criteria utilized in the photo-interpretation were the following: 1) the differential erosion, excepted peneplanized areas, constituted the main criterium of identification of the various lithologies; 2) the drainage pattern reflecting the structural situation of subjacent rocks; 3) the textural relations, important in the distinguishing of particular lithological types which present special textural patterns. The geology of the area is represented by metamorphic rocks which predominate in the whole region with the exception of the eastern and northern parts where they are covered by cenozoic sediments and by those of the Paraná Basin respectively. With regard to the metamorphic rocks a more and more increasing grade of metamorphism is noted from west to east. In a general way, the structures are directed NE or E-NE, comprising main faults, the shape of granitic bodies, the lines of crests and the patterns of the intercalations. The traces of fractures, follow a parallel direction to xislosity, there being also a conspicuous system in a NW direction, more recent and associated, in certain regions, to diabase diques. The dip of planar elements arc practically always toward NW, whereas the axes of the folds plunge toward NE. Due to the regional tendency of structures, one may suggest that the main effort causing folding of the Açungui Group proceeded from NW. while there had been a stable and rigid zone to the E or SE side. The Açungui Group should then have constituted a miogessinclinal whose diastrophism has produced sloping folds toward the foreland. The granites, interpreted as result of the palingenesis, were introduced in the metasediments in anticlinal nucleus at the same time, or somewhat later, after the main diastrophism. The first granites of syntectonic nature are concordant with the country rock structures. Those of a later age, of post-tectonic nature, cut through the structures in a discordant way.