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Palynological investigations of the mid-Cretaceous, delta-influenced Malha Formation and superjacent transgressive Galala Formation exposed at Gebel El Minshera, north Sinai, Egypt, have yielded a sparse but biostratigraphically useful record of spores, pollen, and rare dinoflagellate cysts. A representative of the pollen genus Tricolporites, recovered 18 m above the base of the Malha Formation, is post-Aptian in age. An interval comprising the upper Malha Formation and lower Galala Formation is dated as middle Albian/middle Cenomanian based on the occurrence of Elaterosporites klaszii at the base and Afropollis jardinus at the top. A palynoflora from the upper Malha Formation, which includes ephedroids as well as Elaterosporites, has affinities with the Albian-Cenomanian Elaterates Province. The presence of palynomorphs associated with active fluvio-deltaic settings supports a proximal deltaic environment for the deposition of the Malha Formation, with the superjacent Galala Formation representing a subsequent marine flooding of the delta. A distinctive monospecific assemblage of the dinoflagellate cyst Subtilisphaera senegalensis in the upper part (Cenomanian) of the Galala Formation reflects an ecologically stressed, marginal-marine environment. This assemblage constitutes the first record of the mid-Cretaceous Subtilisphaera ecozone in Egypt and indeed east of Morocco, and in deposits as young as Cenomanian. The Malha and lowermost Galala Formations are characterized by type III-VI kerogen, which is gas prone but having little potential to produce hydrocarbons. Spore-pollen color indicates thermal maturity at the transitional to over-mature level, which is anomalously high when compared with equivalent deposits in the region.