Ti-containing zeolites TS-1 and Ti-beta are investigated as catalysts for the oxidation of cyclopentene with dilute hydrogen peroxide in organic solvents, at 313 K. Under the same conditions TS-1 is more active than Ti-beta catalyst. It is shown that the activity and selectivity of the system H2O2/Ti-zeolite in this reaction greatly depend on the nature of the solvent (protic or aprotic).