Integrated aircraft structure in composite material that comprises a skin and stringers (1), with the skin comprising a string part (5) and a basic skin (3), which structure further comprises U-shaped elements (15) each of which comprises in its turn two L-shaped sections (4a+5a and 4b+5b) together with the skin part (5), in such a way that these U-shaped elements (15) fulfill two structural functions in said structure at the same time, acting as frame feet and as skin, providing an integrated fuselage structure without rivets or joints. The invention also relates to a manufacturing process of an integrated aircraft structure in composite material.