A method for assembling two parts, referred to as first and second parts, the first part being produced from composite material with fibrous reinforcement embedded in a thermosetting or thermoplastic matrix, the method comprising the steps of: obtaining the first part comprising, on all or part of an outer surface, a first amorphous thermoplastic film; positioning the first part and the second part such that the first amorphous thermoplastic film is placed opposite the second part; introducing a thermosetting resin between the first amorphous thermoplastic film and the second part; at least partially polymerising the thermosetting resin. When the two parts comprise an amorphous thermoplastic film, the parts are positioned such that the respective amorphous thermoplastic films are placed opposite each other, and the thermosetting resin is introduced between the amorphous thermoplastic films.