The border between Indonesia and Vietnam is a maritime border located in the South China Sea

South China Sea

The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around...

 to the north of Indonesia's Natuna Islands. The two countries signed an agreement to determine their continental shelf boundary on 26 June 2003 in Hanoi

Hanoi

Hanoi , is the capital of Vietnam and the country's second largest city. Its population in 2009 was estimated at 2.6 million for urban districts, 6.5 million for the metropolitan jurisdiction. From 1010 until 1802, it was the most important political centre of Vietnam...

, Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

.

Although located near, the border is not located in the Spratly Islands

Spratly Islands

The Spratly Islands are a group of more than 750 reefs, islets, atolls, cays and islands in the South China Sea. The archipelago lies off the coasts of the Philippines and Malaysia , about one third of the way from there to southern Vietnam. They comprise less than four square kilometers of land...

 area and Indonesia does not have any claims over the islands.

The border

The Agreement between the Government of the Republic of Indonesia and the Government of the Socialist Republic of Vietnam concerning the delimitation of the Continental Shelf Boundary was signed on 26 June 2003 in Hanoi, Vietnam, by Indonesia's Foreign Minister Hasan Wirajuda and his Vietnamese counterpart Nguyen Dy Nien.

The agreement defined the continental shelf

Continental shelf

The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...

 boundary of the two countries as the imaginary straight line located between the two terminal points - namely Point 20 and Point 25 - of the 1969 continental shelf agreement between Indonesia and Malaysia

Indonesia-Malaysia border

The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca, in the South China Sea and in the Celebes Sea.The...

 with four turning points in between.

Point	Longtitude (E)	Latitude (N)	Remarks
Continental shelf boundary end and turning point coordinates
20	105° 49' 12"	6° 5' 48"	This is the northern terminus of the Indonesia-Malaysia continental shelf boundary Indonesia-Malaysia border The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca, in the South China Sea and in the Celebes Sea.The...  (off the East Coast of Peninsula Malaysia segment) agreed to in 1969; eastern-most point of the Malaysia-Vietnam area of overlapping claims Malaysia-Vietnam border Malaysia and Vietnam are two South-east Asian countries with maritime boundaries which meet in the Gulf of Thailand and South China Sea. The two countries have overlapping claims over the continental shelf in the Gulf of Thailand...
H	106° 12'	6° 15'
H1	106° 19' 01"	6° 15'
A4	106° 39' 37.67"	6° 20' 59.88"
X1	109° 17' 13"	6° 50' 15"
25	109° 38' 36"	6° 18' 12"	This is also the northern terminus of the Indonesia-Malaysia continental shelf boundary Indonesia-Malaysia border The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca, in the South China Sea and in the Celebes Sea.The... (off the northweast coast of Borneo segment) agreed to in 1969; western terminus of Malaysia's continental shelf off the coast of Borneo as asserted in its 1979 map