Dielectric　layer　photonic　crystal　filter　structures　in　waveguide　are　optimized　by　the　quadratic　response　surface　methodology.　The　optimization　model　of　the　filter　is　established　on　the　basis　of　the　analysis　which　is　conducted　with　the　aid　of　the　response　surface　methodology.　The　model　is　solved　using　sequential　quadratic　programming　and　the　optimal　parameters　are　obtained.　Examples　demonstrate　it　is　effective.