Heck reaction catalyzed by palladium(II) attached polycarbosilane is reported. Polycarbosilane (PCS),which is an organic-inorganic hybrid polymer containing both Si and C in its back bone structure, was synthesized by the polycondensation of trichloromethylsilane and trimethoxyvinylsilane in the presence of sodium metal. Palladium acetate was attached to the polycarbosilane (Pd-PCS) and its catalytic activity was investigated. Heck reaction in which C–C coupling between aryl halides or vinyl halides and activatedalkenes in the presence of a base has been selected for the study. Palladium ions supported on PCS havebeen used as a catalyst for the first time and it efficiently catalyzed Heck reaction and an yield of 75–90%was obtained with different substrates. For comparison, catalytic activities of Pd ions supported on SBA-15, activated charcoal and amorphous silica were also investigated. Results indicate the superior activityof Pd-PCS.