This data set consists of analytical results from the HAWK Pyrolysis and TOC instrument for 161 bulk samples from Mesozoic to Cenozoic strata at 20 DSDP-ODP sites in the South Atlantic region, from the Weddell Sea in the south to the Demerara Rise in the north, and in the Mozambique Ridge. Based on a revised chronostratigraphic and paleoenvironment framework (Setoyama and Kanungo, submitted), our pyrolysis results, combined with data published by previous studies, allow us to identify seven Mesozoic source-rock intervals: two in the Southern South Atlantic (SA), one in the Central SA and four in the Equatorial SA. Furthermore, these data also provide an estimate of the source-rock potential and quality of the identified intervals, which are influenced by depositional environments. A significant portion of the pyrolysis data is affected by the mineral matrix effect (MME) that artificially lowers the estimated potential and quality of source rocks. Further analyses are therefore required to correct the MME and for the proper identification of organic matter to ensure the reliable determination of organofacies, thereby facilitating improved source rock system evaluation.