Disclosed is a method for manufacturing a horological component according to which a silicon-based piece having the desired shape of the horological component is produced and the piece is subjected to a thermal oxidation and deoxidation treatment to remove a predetermined thickness of silicon in order to increase the mechanical strength of the piece. This method is characterized in that the thermal oxidation and deoxidation treatment is carried out in several steps, each step including a thermal oxidation phase followed by a deoxidation phase.