The invention relates to a novel process for the conversion of a feedstock comprising at least one sugar to 5-hydroxymethylfurfural, in which said feedstock is contacted with one or more catalysts of the family of the homogeneous sulphonic acids in the presence of at least one aprotic polar solvent, used alone or in a mixture, at a temperature comprised between 30° C. and 200° C., and at a pressure comprised between 0.1 MPa and 10 MPa in which said catalysts are selected from the compounds of general formula