A method for manufacturing annular sectors of an air intake lip includes arranging a revolution-shaped blank facing a three-dimensional forming surface of a die of a hydroforming tool, the three-dimensional surface including at least two plunging cavities spaced from each other along a circumferential direction, forming an air intake lip preform in one piece by hydroforming the revolution-shaped blank on the three-dimensional surface of the die, the air intake lip preform having in section a U-shape and including a plurality of crenellated portions each delimited by a plunging cavity, the production of a plurality of cutouts in the air intake lip preform so as to divide the preform into a plurality of annular sectors, each cutout including the removal of a sacrificial portion at the level of a crenellated portion so as to form two adjacent assembly edges with one of the two adjacent assembly edges including a plunging.