Graf-Askania and LaCoste-Romberg surface-ship gravity meters were installed on the Saclant ASW Research Center's R. V. Aragonese, and performance of the two instruments was compared during a 3-week cruise. Known bottom-meter gravity anomalies in portions of the surveyed area provided checks on the accuracy of the measurements. Differences with respect to meter drift, uniformity of calibration factor, reliability of measurements in calm seas and in moderately rough seas were investigated. Good results were obtained with both meters in calm seas. The Graf-Askania platform permitted reliable measurements to be made in moderate seas. The LaCoste-Romberg measurements were in error because of inadequate response of the accelerometers to long-period components of ship motion. The drift rate of the LaCoste-Romberg meter was negligible, its calibration factor did not vary significantly with time, and the time lags caused by the ship's motion were short. The Graf-Askania meter had a relatively large drift rate, and the time lags were relatively long.