A dynamic mechanical analysis of silica filled closed-cell microcellular ethylene-octene copolymer vulcanizates has been performed at four frequencies i.e., 3.5, 11, 35 and 110 Hz in the temperature range from - 100degreesC to + 100degreesC. A linear relationship of log storage modulus vs. log density for both solid and closed cell microcellular vulcanizates was observed. The slope is found to be temperature dependent. The relative storage modulus decreases with decrease in relative density. Master curves of modulus vs. log (reduced strain rate) are formed by time-temperature superposition metho using shift factors, calculated from Arrehenius equation for solid and microcellular vulcanizates. A strain dependent isothermal dynamic mechanical analysis was carried out. The effects of the blowing agent loading on storage modulus (E') and loss tangent (tan delta) were also studied. Cole-Cole plots of microcellular vulcanizates show a circular arc relationship with density.