Giant earthquake and tsunami widely disturbed ionospheric plasma via acoustic gravity waves. During the M 9.0 2011 off the Pacific coast of Tohoku earthquake, the ionospheric disturbances were generated by co-seismic epicentral ground/sea surface motion, Rayleigh-wave traveling, and tsunami-wave traveling. In addition, seismo-tsunamigenic ionospheric hole, widely sudden depression of ionospheric total electron content, was observed. The ionospheric hole gradually disappeared within roughly a few tens minutes.