Let G be a simple graph and let G- denote its complement. We say that G is integral if its spectrum consists of integral values. Let Kxa, yb = Ka,a,...,a,b,b...,b be the complete m-partite graph with xa + yb vertices where x and y are positive integers and m = x + y. In this work we consider integral graphs which belong to the class ?Kxa,yb for any ? > 1 and a > b where mG denotes the m-fold union of the graph G.