We investigated the topographic changes around the Gamo Lagoon in Miyagi Prefecture after the 2011 off the Pacific coast of Tohoku Earthquake and Tsunami, using digital elevation models （DEMs） combining terrestrial and submarine topography. The models were created from existing DEM, airborne light detection and ranging （LiDAR） data, nautical charts, and the digital surface model （DSM） generated by structure from motion （SfM） software. In the study area, the erosion during the tsunami and the deformation for approximately two and a half years after the tsunami occurred mainly in the upper shoreface and beach. The study area showed a sedimentation trend after the tsunami, and the barrier width increased because of the successive accretion of berms formed by inner bars migrating onshore and eventually welding onto the beach. The widening of the barrier and the shrinking of the upper shoreface observed after the tsunami were considered beach ridge plain developments that occur when sediments are abundantly supplied to wave-dominated coasts. The faster recovery of the barrier in the study area compared to that of the Idoura coast may have been due to the absence of artificial structures in the former that prevented the longshore sediment transport.