Given a graph G, let the set C be the collection of all color classes of all possible χ-coloring of G. The subset D of C is the collection of color classes which are dominating sets of G. The maximum cardinality of such D is called dominating color class number of G. In this paper, the dominating color class number is found for several classes of graphs, as well as, general bounds and characterization. The relation between dominating color class number with other parameters of graph G has also been discussed