The Neoproterozoic Paraguay Belt comprises a thick sedimentary succession that was deposited and deformed along the southeastern margin of the Amazonian Craton. The stratigraphy consists of a lower succession of glaciogenic diamictites and turbidites related to the late Cryogenian glacial event, which is overlain by carbonates of the Corumbá and Araras groups. They are in turn overlain by younger glacial rocks deposited during the Ediacaran glacial age. The uppermost succession is composed of sandstones, siltstones and arkoses of the Alto Paraguay Group. This sedimentary sequence represents a passive margin that was deformed during late Neoproterozoic-Cambrian epoch.The cap dolomite of the Araras Group yielded a Pb/Pb isochron age of 633±25 Ma and the Tamengo Formation is constrained by a U-Pb zircon age of 543±25 Ma from an ash bed. Carbon, oxygen and strontium isotopic data are presented for different carbonate sections.