Results of precise gravity surveys obtained through cooperative measurements by the Working Group for Gravity Survey and Precise Levelling in Japan and also the Working Group for Comparing the Gravimeters in Japan are summarized in the present paper. It was ascertained, as a result, that reliability of a single field measurement by means of a LaCoste & Romberg gravimeter (model G) was to be ±0.02-0.03 mgal. On the basis of the obtained results, the following points are discussed in the present paper. (1) Accuracy of gravity survey by means of a LaCoste & Romberg gravimeter. (2) How to use a LaCoste & Romberg gravimeter in gravimetric field survey. (3) Some problems to be checked and investigated in near future in order to raise the accuracy of gravity survey.
