For　seismic　response　control　for　the　system　with　distributed　parameters,　the　motion　control　equation　of　the　system　with　distributed　parameters　is　presented　and　sequential　optimal　modal　control　algorithm　is　derived.　Due　to　the　full　state　requirement　of　sequential　optimal　modal　control　algorithm,　the　full　state　observer　is　proposed.　Then　the　full　state　of　the　system　under　earthquake　is　reconstructed　by　the　seismic　response　of　the　system　easily　measured　by　feedback　sensors.　Therefore,　the　seismic　response　control　for　system　with　distributed　parameters　is　realized　in　the　actually　engineering　by　using　the　sequential　optimal　modal　control　algorithm　based　on　full　state　observers.　A　seismic　response　control　case　of　the　isolated　330　KV　voltage　transformer　is　analyzed　by　adopting　sequential　optimal　modal　control　algorithm　and　sequential　optimal　modal　control　algorithm　based　on　full　state　observers　respectively,　suggesting　that　the　two　control　algorithms　have　the　favorable　control　efficiency　for　the　system　with　distributed　parameters　under　earthquake　and　the　displacement　of　isolation　layer　and　acceleration　of　upper　voltage　transformer　are　decreased　in　different　degree.　In　addition,　the　sequential　optimal　modal　control　algorithm　based　on　full　state　observers　can　control　the　seismic　response　of　the　system　with　distributed　parameters　by　the　feedback　seismic　response　measured　easily　and　has　the　same　control　effect　with　sequential　optimal　modal　control　algorithm　adopting　full　state　feedback.