Abstract A kinetic study of hydrogen transfer and isomerization reactions has been carried out for cyclopentene and cyclohexene. For both cycloolefins, the limiting step of hydrogen transfer is the hydride ion transfer. Isomerization of cyclohexene is rate limited by the proton transfer from a methylcyclopentyl cation to a cycloolefin molecule. Decay parameters have been determined as a function of temperature. Activation energies have also been measured.