In underwater topographic measurement implementing the positioning by a GPS receiver and/or a GNSS receiver and the depth measurement by an echo sounder, an antenna connected to a GPS receiver or a GNSS receiver and a transreceiver of the echosounder are fixed to a vessel. On the other hand, a vessel is subject to movements such as longitudinal swayings (roll), sideways swayings (pitch), and bow swayings (yaw), which result in errors of output data. This study shows techniques to compensate for those errors.