The bomber detonated an explosives-rigged belt in the Qahira area of north Baghdad, also wounding at least 36 people.
Unrest has surged in Iraq this year to levels not seen since 2008, when the country was emerging from a brutal Sunni-Shiite sectarian conflict that claimed tens of thousands of lives.
Attacks have killed more than 3,600 people since the beginning of 2013, according to figures compiled by AFP.