Abstract: By using contradiction, the method of combinatorial analysis and the method of constructing specific coloring, we discussed the vertex-distinguishing E-total (VDET) coloring of complete bipartite graph K_9,n(9≤n≤92),  gave the optimal VDET coloring of complete bipartite graph K_9,n(9≤n≤92), and obtained the VDET chromatic number of K_9,n (9≤n≤92).

Key words: complete bipartite graphs, Etotal coloring, vertexdistinguishing E-total coloring, vertexdistinguishing Etotal chromatic number