Rostojávri is the Sami name for the Rostavatn lake on the border between Norway and Sweden. The Norwegian name for the lake is Rostavatn and the Swedish name is Råstojaure. The lake is located in the municipality of Målselv in county Troms on the Norwegian side of the border, and in municipality Kiruna in county Norrbotten on the Swedish side. The lake lies at 680m and covers an area of 34.24 km - 3,67 of which is in Norway and 30.57 in Sweden.