However, the ICJ ruling is vague on exactly where the final border should be delineated, but gave some of the land to Cambodia, the Bangkok Post reported.
The ancient Hindu temple and surrounding area have been a flash point for around 60 years, since the time of French colonial rule in what was called IndoChina.
A 1962 ruling by the ICJ -- accepted by both countries -- gave the temple to Cambodia and noted that Thailand doesn't claim ownership of the temple, just the area surrounding it.
Today's ruling ends several recent years of often heated dispute between the Asian neighbors over land and access to the isolated mountain temple.
Preah Vihear temple complex is situated on a steep-sided promontory that juts south into the Cambodian plain, making access for Cambodian monks and tourists difficult from Cambodian territory.
Thailand's occupied area has much easier access to the temple, listed as a UNESCO World Heritage Site in 2008.
The latest round of fighting, in early 2011, claimed the lives of more than a dozen Thai soldiers and an unknown number of Cambodians and prompted an ICJ re-interpretation of the dispute.
Thousands of people fled the area before the ICJ ruled in July 2011 that both countries withdraw their troops from the area pending a resolution by the court.
Since then, an uneasy truce has existed.
The Post reported that some of Cambodia's territorial claim was rejected by the court.
The ruling says only that the border should correspond with the natural promontory and that the border needn't follow the watershed, as Thailand has argued.
A dialogue between the two countries -- both members of the Association of Southeast Asian Nations -- now must settle the remaining land issues, Thailand's Ambassador to the The Hague Virachai Plasai said.
Cambodia had only won a small piece of the 1.8 square mile of disputed territory, he said.
"We are still calculating the exact amount," he said. The "small area" mentioned by the court needed to be further interpreted, he said.
Virachai also said both countries should cooperate in taking care of the World Heritage Site.
After the ruling, Cambodian Foreign Minister Hor Namhong, who was in the Netherlands for the ruling, said the ICJ decision was "good enough."
The BBC reported that the ICJ ruling is an interpretation of the court's 1962 judgement and can't be appealed. Both countries have said they will abide the ruling.
But Bangkok's security forces remain on alert after hundreds of protesters petitioned the Defense Ministry on Monday to reject the ICJ's authority over the dispute.
In the Cambodian capital Phnom Penh, about 20 military police were deployed outside the Thai Embassy ahead of the ruling, but there was no sign of protests in the city, the Post reported.