We investigate the behavior of small perturbations around the Kaluza-Klein
monopole in the five dimensional space-time. We find that the even parity
gravitational wave does not propagate in the five dimensional space-time with
Kaluza-Klein monopole provided that the gravitational wave is constant in the
fifth direction. We conclude that a gravitational wave and a U(1) magnetic
monopole do not coexist in five dimensional Kaluza-Klein spacetime.Comment: 10 pages, LaTeX. To appear in Modern Physics Letters