In this thesis, polymer-supported ruthenium catalysts were prepared by using 2%, 5% and 10% DVB poly(styrene-co-divinylbenzene-co-vinylbenzyl chloride) copolymer, reacting with bidentate ligands (2-aminopyridyl and 1, 3-diaminopropane), in which N is an donor atom, with ruthenium trichloride. These catalysts were characterized by FT-IR, XRF, EA and TGA techniques and used as catalyst for cyclooctene hydrogenation. The influence of various parameters such as temperature, time, hydrogen pressure, and the amounts of catalyst and substrate on the hydrogenation has been studied. It was found that all prepared catalysts could catalyze hydrogenation of cyclooctene, giving high yield of cyclooctane (> 95%) at 60 ํC, hydrogen pressure of 5 atm in 5 h. The polymer-supported catalysts have high thermal stability. The ruthenium complex on the polymer support did not leach out after 24 h of immersion in methanol. In addition, it was proved to be able to be reused. Homogeneous ruthenium catalysts: ruthenium-2-aminopyridyl, ruthenium-1, 3-diaminopropane and ruthenium-1, 3-di(2, 6-diisopropylphenyl) aminopropane were also used to catalyze hydrogenation of cyclooctene in the same above condition.