The invention relates to a process for converting a feedstock comprising at least one sugar into 5-hydroxymethylfurfural, wherein said feed is brought into contact with one or more inorganic dehydration catalysts and one or more chloride sources in the presence of at least one aprotic polar solvent alone or as a mixture, at a temperature of between 30° C. and 200° C., and at a pressure of between 0.1 MPa and 10 MPa.