The invention relates to a method for the surface treatment of a biologically inert titanium implant to be placed in contact with a bone of the human body, which involves allowing bodily fluids, such as the inorganic portion of human blood plasma, to naturally deposit, onto the titanium implant, a calcium phosphate film having the formula Ca5(PO4)3(OH), in the form of hydroxyapatite, with a view to rendering the biologically inert titanium biologically active so as to enable a the bone to be chemically bonded to the implant, thus promoting osseointegration, wherein the method includes an operation that involves submerging the titanium implant in a sodium hydroxide (NaOH) solution, the concentration of which is around 10 moles per liter, said submersion causing the formation of a hydrated titanium oxide (HTiO3-) film on the titanium, which in turn causes hydroxyl groups (TiOH) to appear, thereby enabling the deposition of said calcium phosphate film. The method according to the invention is characterized in that the operation of submerging the implant in the sodium hydroxide is preceded by an operation for pickling said implant with a fluoronitric acid solution, in that, during the submersion operation, the temperature of the sodium hydroxide solution is between 60°C and 100°C, and in that the duration of said submersion operation is less than eight hours.Linvention concerne un procédé de traitement de surface dun implant en titane bioinerte destiné à être posé en contact avec un os du corps humain, du type consistant à laisser des fluides biologiques, tels que la partie minérale du plasma sanguin humain, déposer naturellement sur limplant en titane un film de phosphate de calcium, de formule Ca5 ( P04 ) 3 (OH ), sous forme d hydroxyapatite, en vue de rendre bioactif le titane bioinerte afin de permettre une liaison chimique de los avec limplant, favorisant ainsi 1 ostéointégration, le procédé comprenant une opération consistant à immerger limplant en titane dans un
