The magnesium support with the formula MgCl2(THF)(0.32)(Et2AlCl)(0.36) was used for immobilization of salen complexes of titanium [Ti(salen)Cl-2, Ti(salen(O-Me)(2))Cl-2]. The effects of the catalyst composition (i.e. type of titanium complex and type of activator), polymerization temperature, polymerization time, and the effect of comonomer (1-octene) on the activity of the obtained supported catalysts, on the polymer characteristics (molecular weight, molecular weight distribution, melting point), and on the polymer morphology were studied. The findings were compared to those obtained for corresponding unsupported systems. Catalysts immobilization results in considerable changes in catalysts activity and in properties of resultant polymers. The studied supported catalysts are highly active in ethylene polymerization, their activity increases with increasing temperature and lasts at least 2 hours. Their copolymerizing ability towards 1-octene is rather low. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6693-6703, 2009