Security officials say the explosions occurred as worshippers were leaving the Baratha mosque in northern Baghdad after Friday prayers.
There was confusion about the cause of the blasts, as well as the number of explosions. First reports said the explosions were caused by three mortars fired by insurgents, but authorities now say they are sure they were caused by suicide bombers.
Authorities urged Iraqis in the capital to donate blood for those wounded and to avoid gathering in large crowds near mosques and markets, due to the ongoing sectarian violence.
The attack comes a day after a car bomb blast near a Shi'ite Muslim shrine, the tomb of Imam Ali, in the city of Najaf killed at least 10 people.
Thursday in Washington, U.S. Defense Secretary Donald Rumsfeld and his British counterpart, John Reid, urged Iraqi leaders to form a national unity government, as the country's politicians remain deadlocked over senior government posts.
One of the main sticking points is Iraqi Prime Minister Ibrahim al-Jaafari, who is refusing to step down as the Shi'ite nominee for a second term.
Iraq's Kurdish and Sunni Arab leaders say he has not done enough to ease the sectarian violence.
Some information for this report was provided by AFP, AP and Reuters.