Eight people were killed and 22 others were wounded when coordinated car bombings struck an outdoor market in Hillah city, some 95 km south of Baghdad.
Five people lost their lives and 14 others sustained injuries when two cars loaded with explosives went off in a commercial area in Suwayrah city, 40 km south of Baghdad.
Two other car bombs exploded simultaneously in the city of Kut, around 160 km southeast of Baghdad, killing four people and wounding 16 others, a police source said.
Also on Sunday, four people were killed and 13 others wounded when two car bombs ripped through Samawah city, 370 km southeast of Baghdad.
Two other car bombs killed three people and wounded 13 in the city of Diwaniyah, located 130 km south of Baghdad.
In the northern city of Samarra, two people were killed and 15 others were wounded when a bomb targeted a gathering of mourners.
Five other people were killed and 34 were wounded in separate attacks in the southern city of Basra, located about 550 km southeast of Baghdad, and the central towns of Mahmoudiyah and al-Madain, police said.
UN: 1000 killed, over 2000 injured in violence in September in Iraq
No group has claimed responsibility for the blasts, but such bombings bear the hallmarks of Al Qaeda-linked militants in Iraq, which seek to destabilise the central government.
According to the United Nations, almost 1,000 people were killed and more than 2,000 wounded in violence in Iraq in September, making it one of the deadliest months in recent years.