The invention discloses a sliding formwork platform. An inner formwork of the sliding formwork platform is 100 to 220 mm shorter than an outer formwork; the bottom end of the inner formwork is provided with an enclose formwork. Meanwhile, the invention also discloses a sliding formwork construction method of a reinforced concrete tube body. The method sequentially comprises the following steps of building a cast concrete sliding formwork platform; installing a sliding formwork platform control device; casting concrete in a connection position of a tube body foundation and a tube body wall; casting tube body wall concrete to the elevation position of the top surface of an inner floor slab; dismounting the enclosure formwork; performing idle sliding on the sliding formwork platform until the bottom surface of the inner formwork of the sliding formwork reaches the top elevation position of the inner floor slab; erecting a formwork erecting scaffold inside the tube body; casting concrete of the inner floor slab and inner structure beams. During the sliding formwork platform construction, the simultaneous concrete casting of the inner floor slab, inner structure beams and the tube body wall can be realized; the integrality of the reinforced concrete tube body is ensured; the construction technical difficulty is reduced; the construction period is effectively shortened.