Ventnor is a seaside resort established in the Victorian era on the south coast of the Isle of Wight, England. It lies underneath St Boniface Down (which, at 241 metres, is the highest point on the Isle of Wight), and is built on steep slopes and cliffs leading down to the sea. The higher part is referred to as Upper Ventnor; the lower part, where most of the amenities are located, being known as Ventnor. Ventnor is sometimes understood as including the coastal villages of St. Lawrence to one side and Bonchurch to the other.
The sheltered location on the cliff of the Island's south coast means the area experiences a microclimate with more sunny days than much of the British Isles, and fewer frosts. This has allowed many species of subtropical plant to be successfully planted and maintained. Ventnor Botanic Garden is particularly notable.