Vickers microhardness as a function of temperature was determined in a series of norbornene-ethylene copolymers synthesized with a metallocene catalyst. The norbornene content in the samples ranges from 31 to 62 mol %, and all of them were found to be amorphous. The possibility of studying the glass-transition temperature by plotting the microhardness-temperature dependencies is discussed in addition to the limits and the reliability of the suggested method. Moreover, a linear dependency between microhardness at different temperatures and glass-transition temperature was established. (C) 2003 Wiley Periodicals, Inc.