In order to know gravity anomalies at sea, measurement of gravity on islands has the same importance as measurements on board vessels. In July 1961 and June to July 1962, gravity measurement at sea around the Izu-island was carried out by means of the Surface Ship Gravitymeter, and in cooperation with these operation, gravity measurement on the islands in these area has been carried out at Niizima, Kozushima, Miyakeshima, and Hatsusima island. The results are tabulated in the table I.