To maintain the integrity and ensure the sovereignty of the Unitary Republic of Indonesia, it is necessary to determine the boundary region firmness in Indonesia, especially the sea borders (maritime boundary). From the Indonesian side there are some cases of unresolved maritime borders, one of them is Indonesia towards Singapore's maritime boundary. Maritime boundary between these two country has been agreed to West and Central segments and it still leaves 1 (one) other segment, the Eastern segment, which until now has not been resolved and still being negotiated.
In this study conducted maritime delimitation Indonesia - Singapore on East segment by using the principle of equal distance (Equidistant Principle) and assessed according to the 1982 UNCLOS.
The results of this study was obtained 5 (five) median points which form the median line as the maritime boundary between Indonesia and Singapore. The median line is divided into 2 (two) segments, there are Eastern-1 and Eastern-2 segment due to the region of Trijunction Point. Another thing that is found in this study is the difference in geodetic datum which is used in the Eastern segment compared with the Central segment.