President Tarja Halonen will address the gathering.
Finland's ambassador to the 1975 CSCE, Minister Jaakko Iloniemi, described the final act of the conference as allowing an opening of doors between peoples.
Speaking on YLE Morning TV, Iloniemi said one result of the conference was to provide people with information concerning their political and human rights, especially in communist nations. The right of people to meet their relatives over borders was also recognised and, to some extent, put into practice.
Leaders of all European nations, the United States and Canada took part in the conference in Helsinki's Finlandia Hall in 1975. Only Albania was absent.
The CSCE process was a great political achievement for Finland's President Urho Kekkonen. By hosting such a prestigious conference of world leaders, Finland strengthened its policy of neutrality during the cold war period.
Although the ice froze over again at the end of the decade, the conference did lay the groundwork for the work of the OSCE worldwide.