Finland will become the 31st member of Nato after Turkey's parliament voted to approve its application.
Ednews reports citing Turkish media that Turkey had delayed Finland's bid to join the West's defensive alliance for months - complaining the Nordic nation was supporting "terrorists".
Sweden, which applied to join NATO at the same time last May, is still being blocked by Ankara over similar complaints.
Any Nato expansion needs the support of all its members.
Finland will now be formally admitted into NATO at its next summit, taking place in July in Lithuania.
In a statement following the Turkish vote, the Finnish government said joining the alliance would strengthen the country's security, and improve stability and security in the region.
"As allies, we will give and receive security. We will defend each other. Finland stands with Sweden now and in the future and supports its application," Prime Minister Sanna Marin wrote on Twitter.
Turkish President Recep Tayyip Erdogan gave his approval to Finland's bid earlier this month, praising the country's "authentic and concrete steps" on Turkish security.
But his ongoing hostility to Sweden was clear - as he again accused the country of embracing Kurdish militants and allowing them to demonstrate on the streets of Stockholm.
