The catalytic performance of ruthenium alkylidene complexes bearing tricyclohexylphosphine or 3-bromopyridine ligand in the ring opening metathesis polymerization (ROMP) of fluorine containing monomers, exo-N-4-fluorophenyl-7-oxanorbornene-5,6-dicarboximide (FPhONDI) and exo-N-4-fluorophenyl-norbornene-5,6-dicarboximide (FPhNDI) was investigated. Pure monomers were subjected to ROMP with RuCl2(PCy3)(2)(CHPh) (I), RuCl2(PCy3)(H(2)IMes)(CHPh) (II), RuCl2(3-Br-py)(2)(PCy3)(CHPh) (III) and RuCl2(3-Br-py)(2)(H(2)IMes)(CHPh) (IV). The polymers were fully characterized using NMR, DSC, SEM and GPC. Catalysts I-IV displayed significant ROMP activity, allowing for the synthesis of the corresponding polymers with polydispersity indices (PDIs) in the range of 1.4-4.0. High molecular weight polymers (Mw up to 4.95 x10(5)) were prepared in yields up to 90 %, depending on the initiator and monomer used.