Abstract: A method for producing high strength cement conglomerates is disclosed. Cement conglomerates (pastes, mortars, concretes and the like) having improved mechanical characteristics, are produced in accordance with the invention by adding to a mix of water, binder and aggregates a admixture or composition containing: (1) a polymer obtained by polycondensation of an aldehyde with a water-soluble sulphonic acid of the aromatic series, and (2) a product of the hydrolysis of starch obtained from raw vegetable materials such as maize, wheat, rice, potatoes, etc. Water soluble inorganic electrolytes may advantageously be added to the admixture for significantly improving the characteristics of fluidity and cohesion of the fresh mix, and the characteristics of strength of the hardened mix.