The Pentagon said on Monday the agreement will bolster the search for more than 200 girls kidnapped by Islamist rebel group Boko Haram.
The U.S. military is flying manned and unmanned surveillance aircraft over Nigeria, but had been unable to directly share intelligence with Abuja because it had not established protocols with the government.
Pentagon spokesman Colonel Steve Warren said that agreement was struck over the weekend.
"We have finalized an agreement with the Nigerians to share intelligence with them - specifically intelligence relating to the kidnapped girls," Warren told reporters.
While the agreement would allow the U.S. military to share some intelligence - including aerial imagery - with Nigeria, it did not mean that all raw U.S. intelligence gathered could be shared, Warren added.
The Pentagon's announcement follows a meeting in Paris over the weekend where West African leaders agreed to work together to combat Boko Haram, saying the group had become a shared threat.
Boko Haram has killed more than 3,000 people in its war to establish an Islamic state in mostly Muslim northeast Nigeria.
Nigeria's neighbors Chad, Cameroon, Niger and Benin, and Western officials, met in Paris to flesh out a plan enabling them for the first time to share intelligence, coordinate action and monitor borders.