The sailors were aboard the vessel Armadah Tuah about 42 miles off the southern Nigerian state of Bayelsa when they were taken hostage Feb. 17, RIA Novosti reported Tuesday.
The Foreign Ministry said the hostages were released Monday and were "free and well," quoting the ship's manager, the Nigerian branch of the Malaysian company Armadah Navigation.
The hostages were Ukrainian, Indian and Russian nationals.
The ministry statement did not indicate if any ransom was paid.
Some 58 incidents of piracy occurred off the coast of Nigeria in 2012, with 207 crew members taken hostage.