The Early Cretaceous Wealden Group of Swanage Bay, Dorset, southern England, comprises two formations, a lower Wessex Formation and an overlying Vectis Formation. Presently only part of the former is exposed and here its stratigraphy, sedimentology and palaeontology are redescribed. Recent work on the Wealden Group of the Wessex Sub-basin has focused either on the Barremian – earliest Aptian of the Isle of Wight, or on the Wealden Group of Dorset in a broader context. Consequently, the Wealden Group of Swanage Bay lacks detailed analysis and description. In the 200 years since the first account of the geology and stratigraphy of Swanage Bay, slumping and vegetation growth have dramatically concealed the upper part of the Group at this previously well-known locality. A stratigraphical framework with assigned marker beds is established here for the first time allowing for the precise placement of new palaeontological discoveries. Analysis of the palaeobotanical and microvertebrate remains recovered from the recorded section permits a more accurate reconstruction of the Early Cretaceous Wessex Formation ecosystem of east Dorset.