The invention concerns a process for preparing a hybrid organic-inorganic material (HOIM) with phosphorus-containing bridges between the surface of an inorganic substrate containing an element M and one or more organic groups of the covalent M-O-P-R type, said process using, as a precursor for said organic group or groups, at least one organophosphorus acid halide with formula R.sub.xP(O)X.sub.y in which x=1 or 2, y=3-x, X being a halogen and R designating at least one organic alkyl, aryl or aryl-alkyl group. Non-exhaustive applications for the hybrid organic-inorganic material obtained by the process of the invention are in the fields of anti-corrosion, lubrication, microelectronics, nanotechnologies, composite materials, heterogeneous catalysis, supported catalysis, depollution and biomedical applications.