Militants bombed two crowded markets in Baghdad province on Thursday, killing at least 19 people and wounding some 50 others, officials said.
Four bombs in Saba al-Bur north of the capital killed at least 12 people, while another in the predominantly Sunni neighbourhood of Dura in south Baghdad killed seven, the officials said.
Militants in Iraq often bomb areas where crowds of people gather, and have targeted markets, football fields, cafes mosques, weddings and funerals this year.
Iraq is witnessing the worst violence since 2008, when the country was just emerging from a brutal sectarian conflict.
There are persistent fears that Iraq will return to the all-out Sunni-Shiite sectarian violence that peaked in 2006-2007 and killed tens of thousands of people.
With the latest violence, almost 700 people have been killed this month and over 4,500 since the beginning of the year, according to AFP figures based on security and medical sources.
Diplomats and analysts say the Shiite-led government's failure to address the grievances of the Sunni Arab minority, who complain of political exclusion and abuses at the hands of the security forces, has driven the spike in violence this year.
The civil war in neighbouring Syria has also fuelled sectarian tensions in Iraq.