The heterogenous polymerization of methyl methacrylate in the presence of cuprous oxide was studied. Adsorption measurements of stearic acid from benzene solution onto the surface of Cu2O were carried out. The specific surface area of cuprous oxide as obtained from the extrapolation to the concentration of monolayer surface coverage in the adsorption isotherm was compared with that evaluated from the BET-equation. Sedimentation volume and sedimentation rate of the variably surface modified Cu2O samples were determined. It was found that the surface modification of Cu2O enhances its catalytic effect in the heterogenous polymerization of methyl methacrylate up to monolayer surface coverage. The viscosity average molecular weights M̄v of the respective polymers as well as the apparent activation energy of the polymerization process were correlated with the reaction parameters.