Ring-opening metathesis polymerization(ROMP) of cycloolefins has emerged as a powerful tool for macromolecular engineering,among which the ring-opening metathesis polymerization(ROMP) of dicyclopentadiene(DCPD) gains widespread interest recently.An overall discussion about the catelysts used in the ROMP of DCPD,most of which are transition-metal complexes,is done in this paper.