An agrochemical formulation in the form of an oil suspension characterized in that it contains as essential elements of the formulation (percentages by weight related to the total weight of the formulation) at least; a herbicide of the sulphonylurea type at a concentration of 0.5-50%, preferably 2-30%, a paraffin mineral oil at a concentration of 10-75%, preferably without the existence of any other type of mineral or vegetable oil in the formulation and the concentration of mineral oil being 40-60%, an organomodified silane compound at a concentration of 5-40%, preferably 10-25%, with the existence of other coformulants until reaching 100% by weight of the formulation.