Under the contract, Westinghouse Electric will be responsible for yearly supply of fuel for one unit during the four-year period of 2016 to 2019.
The fuel will be produced by Westinghouse at its facility in Västerås, Sweden.
Westinghouse Northern Europe vice president and managing director Johan Hallén said: "Their continued confidence shows that they have been satisfied with the quality that Westinghouse delivers, and strengthens our position as a boiling water reactor fuel supplier to the European market."
The Olkiluoto features two boiling water reactors (BWR), which were designed and built by ASEA-ATOM.
Westinghouse is a single-source global nuclear fuel provider for pressurized water reactors (PWRs), including Russian-designed VVER reactors, as well as BWRs and advanced gas-cooled reactors (AGRs).
The company currently operates 10 nuclear fuel manufacturing locations around the world, including two sites in Europe and is also fueling 145 PWR and BWR plants.
