(EN) The invention relates to a continuous method for production of polyoxymethylene homo- or co-polymer by mass polymerisation of the monomers in the presence of cationic-effect initiators and, optionally, in the presence of regulators. During the polymerisation, both monomers and polymer are in the molten form, the polymer is then deactivated, the melt withdrawn, cooled and granulated. The invention is characterised in that the polymer is withdrawn, cooled and granulated under elevated pressure and in the presence of a liquid.