Abstract The Veracruz Basin occurs along the southwest margin of the Gulf of Mexico. It is bounded on the north by the Trans-Mexican volcanic belt, on the west by the Sierra Zongolica fold-thrust belt, and on the south by the Saline Basin, and it is separated from the Gulf of Mexico by structural highs associated with the Los Tuxtlas and Anegada Volanoes. The Veracruz Basin lies on transitional crust weakened by a Triassic-Jurassic transform margin along which Yucatán (the Maya block) moved south during the opening of the Gulf of Mexico. During the latest Jurassic and Cretaceous, this area comprised a passive margin with a carbonate platform. Laramide east-directed thrusting in the Sierra Zongolica initiated clastic deposition and crustal loading that probably led to development of a foreland basin along the eastern limit of thrusting. Eocene to mid-Miocene basin formation may have been a result of continued crustal downwarping in the foreland of the Zongolica thrust belt or of initiation of left-lateral extension, based on analogy to the Tehuacán Basin to the west. Initiation of the Cocos-Nazca spreading center during the mid-Miocene led to oblique convergence between the Farallon and North American Plates and caused left-lateral movement along the Motagua-Polochic system, contractional deformation in the Chiapas fold-thrust belt, and structural inversion and possible right-lateral transpression in the Veracruz Basin. The basin continued to deepen as it deformed internally, collecting as much as 12 km of Tertiary sediments. Folds in the Catemaco area of the southernmost Veracruz Basin rotate, without tear or lateral faulting, from northwest-southeast to northeast-southwest. The Catemaco area is considered to be on the northwest limb of a regional orocline extending 400 km from San Andres Tuxtla, Veracruz, to Tenosique, Tabasco, and characterized by Neogene growth-thrust folds. Marine carbonates of the Jurassic Tepexilotla Formation and the Cretaceous Orizaba, Maltrata, Guzmantla, and Méndez/Atoyac Formations may have generated both oil and gas, and Tertiary source rocks produced biogenic gas. Reservoirs exist in Cretaceous carbonate and siliciclastic units and in Tertiary sandstones. Migration most likely occurred along the top Upper Jurassic Tepexilotla Formation sandstone, in the top mid-Cretaceous Orizaba Formation carbonate breccias, and in sandstones throughout the Tertiary section. Interbedded shales and tight carbonates form seals. Modeling suggests that oils found in the basin generated and began migration in the Late Cretaceous about 80 Ma and that generation continues today. Thermogenic gas generation may have begun about 48 Ma, and biogenic gas is probably generating today.