Another 127 people were injured in the attack in the predominantly Shia district of northern Baghdad at around 7pm (5pm Irish time).
A motorcycle rickshaw loaded with explosives that were covered with fruit and vegetables caused a massive blast, with women and children among the casualties and dozens of market kiosks damaged.
The attacker jumped off the rickshaw in the middle of Mraidi market and managed to escape before the bomb was set off.
The market area was closed off by Iraqi security forces in the aftermath of the bombing.
The bombing was the latest attack in the runup to the planned pullout of US troops from Iraqi cities, towns and villages by 30 June.
Violence has dropped markedly in Iraq in recent months, with May seeing the lowest Iraqi death toll since the 2003 invasion. But attacks remain common, particularly in Baghdad and the main northern city of Mosul.
