Optimized ring-opening metathesis polymerization (ROMP) conditions for cyclohexenyl norbornene (CHNB) have been determined. ROMP of CHNB was carried out with ruthenium trichloride hydrate and ruthenium benzylidene catalysts. The effects of mol % catalyst, type of catalyst, use of a dissolution aid (for RuCl3 ??2O), reaction time and temperature on conversion and gel time were investigated. ROMP with 0.0027 mol % ruthenium benzylidene at room temperature gave CHNB conversions ranging from 97 to 99% with gel times of ca. 24 min. With ruthenium trichloride hydrate and using ethanol as a dissolution aid, only 60-80% conversions with gel times of ca. 43 min occurred at 55-60℃. The obtained polyCHNB's were crosslinked or not, epending on ROMP conditions. All polyCHNB' exhibited 5% weight loss at ca. 420 and 430℃ under nitrogen and air atmospheres, respectively. The DSC measured glass transition temperature of all polyCHNB samples was 105℃.