Copolymerizations of ethylene with propene, of ethylene with 1-hexene and of propene with 1-hexene were carried out at 40°C under atmospheric pressure with SiO2-, Al2O3- and MgCl2-supported metallocene catalysts using common alkylaluminiums as cocatalyst. From a detailed analysis of copolymers by 13C NMR, all the copolymers obtained were found to be random (r1·r2 ≤ 1). When ethylene was used as a base monomer, the polymer yield markedly increased with increasing comonomer concentration. The molecular weight of the copolymers obtained in this study were found to be much higher than those obtained with homogeneous Kaminsky-Sinn catalysts. Whereas, the polydispersity (Mw/Mn) of the copolymer is dependent on the combination of monomers as well as on the inorganic compounds used as carrier.