Abstract Multiple petroleum systems and numerous source–reservoir pairs are recognized in offshore Cabinda. In Block 0, the principal petroleum systems are the Bucomazi–Vermelha(!), Iabe/Landana–Pinda(!), and Malembo–Pinda(!). These systems arise from three prolific source rock units: the lacustrine Lower Cretaceous Bucomazi Group, the marine Upper Cretaceous–lower Tertiary Iabe and Landana Formations, and the marine Tertiary Malembo Formation. Cabinda oils can be separated into source families on the basis of composition using various analytical techniques. Quantitative biomarker analysis is useful in differentiating the genetic origin of these oils, especially when they have multiple sources. The Lower Cretaceous Bucomazi source rock, the major contributor to the oil produced in offshore Cabinda, contains four units rich in type I kerogens: the lower Bucomazi and time-equivalent Erva Formation, the middle (“organic”) Bucomazi, and the upper Bucomazi. These units together average a high SPI of 33 tons HC/m 2 rock. Oils generated from the Bucomazi are trapped in pre-rift Lucula sandstones, synrift Erva sandstones, and lacustrine Toca carbonates, and also have migrated through salt windows into the marine postrift Pinda, Vermelha, and Iabe. The marine Upper Cretaceous Iabe and Paleocene–Eocene Landana shales are also excellent source rocks in the outer shelf to slope depositional environments. They consist of type II kerogen with high average SPIs (>15 tons HC/m 2 rock). Oils from these source rocks have migrated primarily to reservoirs in the Pinda and Malembo. The Malembo has fair source potential in western offshore Cabinda (Blocks B and C), with type II and II–III kerogen and moderate SPIs (5–15 tons HC/m 2 rock). Oils generated from the Malembo have been found in Pinda and Malembo reservoirs. Effective seals are plentiful and include Bucomazi and Toca shales, the Loeme Salt, anhydritic and argillaceous beds in the Pinda Group, marine shales atop a transgressive Cenomanian–Eocene megasequence (Vermelha, Iabe, and Landana Formations), and Malembo shales. Just as the locations of the source facies have shifted westward through time, the generative depressions have also moved westward following the evolution of the west African margin. Oil generation in Block 0 has been active from the Late Cretaceous to the present, with the most recent generation occurring in the west. The petroleum systems have evolved from east to west with differences in source origins, reservoirs, and timing.