Ethylene-norbornene copolymers (ENC) with similar to 50%, similar to 25% and similar to 15% norbornene (NB) fraction in a wide range of molecular weight were produced by metallocene catalysts. By coupling the gel permeation chromatography (GPC) with the intrinsic viscosity data in 1,2,4-trichlorobenzene (TCB)at 150 degrees C, the Mark-Houwink parameters of ENC were determined and compared with previous classical analysis using polyethylene's relative parameters. The results indicated that parameter K was considerably increased with decreasing NB fraction in ENC but parameter a was only increased slightly. Furthermore, the structure characteristics and correlative rheological parameters of resultant ENC were also calculated and discussed by the Stockmayer-Fixman analysis. (C) 2008 Wiley Periodicals, Inc.