The solid support was iodonated poly(siloxane) surface prepared by condensation reactions of (EtO),Si with (MeO),Si(CH,),I. The supported metalloporphyrins were employed as catalysts for the oxidation reactions of 1-octene and of cyclohexene. NaBH, was used to reduce [MnIII(TPyP)]+ and [Sn1V(TPyP)]2+ back to their catalytically active Mn” and Sn” forms, respectively. Contrary to their homogeneous counterparts, both of the supported metalloporphyrins catalysed the cyclohexene oxidation reaction to yield only 2-cyclohexen-l-one with no other products over a reaction time of 10 h. In addition to cyclohexene oxidation, the supported [MnIII(TPyP)]+ catalysed I-octene oxidation as well, whereas the supported [Sn’“(TPyP)]2+ was inactive for the oxidation of 1-octene.