Abstract: Novel oligomerization catalysts comprising cobalt oxide on carbon in admixture with certain other catalyst supports, such as refractory oxides, i.e. alumina, silica alumina and molecular sieves and the like are herein disclosed. The preparation of said novel catalysts is likewise disclosed and the use of said catalysts in propylene oligomerization reactions is hereby described and claimed. The novel oligomerization catalysts are produced by: (a) impregnating activated carbon with a solution containing a cobalt amine complex; (b) treating the impregnated activated carbon at elevated temperatures in order to decompose the cobalt salt to cobalt oxide; and (c) thereafter admixing the so-formed cobalt oxide on carbon with a catalyst support material such as bauxite.