A pile hammer for driving down hollow piles from an upper end thereof includes a hollow pile cap adapted to rest and support the hammer on a upper end of the pile being driven. The cap has an anvil surface for receiving blows from a ram which is slidably disposed on a hollow tubular base extending downwardly from the pile cap and having a lower end portion extending into the hollow pile being driven below the level of the pile cap. The ram is slidable on an upper portion of the hollow tubular base and has an annular lower end face adapted to strike the anvil surface of the pile cap when the ram is released to drop from an elevated position above the pile cap. A ram lift system is provided in an upper portion of the hollow tubular base for lifting the ram to an elevated position a selected predetermined height above the pile for release to drop downwardly and strike a driving blow against the anvil surface on the pile cap. The pile hammer is supported completely on the pile being driven and other means of support are not required. Sea water may be used as the operating fluid of the pile hammer and the hammer is operable above or below the water or on dry land. The pile hammer includes a remotely controllable, fluid control system for operating the pile hammer in an automatic or manual mode and the pile hammer does not require a waterproof enclosure.