The present invention concerns a catalyst for the polymerization of olefins, and a method for preparing the same said catalyst constituting an inorganic support material with catalytically active chromium and titanium compounds bound on its surface. The catalyst is prepared according to the invention by bringing the catalytically active metal compounds sequentially in vapor phase onto the support material surface in excess amounts in relation to the binding sites available on the support material surface. The support material temperature is maintained above the condensation temperature of the vapor, preferably above 160.degree. C., and simultaneously sufficiently high so as to achieve the thermal activation energy necessary for the generation of bonds between the support material and the catalytically active material or its compound. To avoid desorption of the chemisorbed compounds, the temperature is kept below approx. 500.degree. C. The activity of a catalyst in accordance with the invention even with very low contents of the catalytic metals is as high as the activity of a catalyst of multiply higher metal contents that has been prepared by the methods of the conventional technoloyg.