Ring-opening metathesis polymerization (ROMP) gel reagents in parallel synthesis were investigated. The use of ROMP in the preparation of surface-functionalized inorganic and organic supports for application in heterogeneous catalysis was also discussed. It was shown that ROMPgels were very useful supports for the immobilization of reagents and scavengers. ROMPgels swelled significantly in a variety of solvents, and their physical properties were finely tuned by the use of cross-linkers in their polymerization.