The JV stated that the as-yet unnamed project is expected to start production in the first half of 2020 and has not disclosed where it will be built.
It forms part of the 1GW of capacity the JV was awarded in the first Russian wind auction in June 2017.
Manufacturer Vestas was named as the preferred supplier for the portfolio but has not yet chosen a model for the 200MW site.
Vestas is working with technology giant Rusnano to set up a blade production facility in Ulyanovsk in the south-west of the country.
It is also independently producing nacelles at its factory in Nizhny Novgorod in western Russia.
Rusnano, meanwhile, formed a joint venture with Spanish firm Windar Renovables and steel company Severstal to build towers for 300MW of wind capacity per year.
Fortum and Rusnano’s 200MW project will follow a 50MW site currently under construction and due to start producing power in the first half of 2019.
The JV said future investment decisions on the 1GW won in June 2017 and a further 823MW won in June 2018 will be made on a case-by-case basis, adding it was too early to say where other projects will be built.
It has, however, signed a non-binding co-operation agreement with the government of Rostov in western Russia to build 600MW of wind capacity between 2019 and 2022.