The blast went off in a busy market street as worshippers were leaving the mosque in the town of Howaider, nearby Baquba, 60 kilometres northeast of Baghdad.
The death toll has rapidly been rising following the attack with an interior ministry official updating the casualty figures showing 26 dead and 70 wounded.
The official said that some of the injured were taken to a US military base near Baquba.
It’s the latest attack in a wave of sectarian violence that has engulfed the country since the bombing of a Shiite shrine in the northern city of Samarra in February.
Hundreds of people were killed in the bombing and was blamed on Sunni insurgents. Bloody reprisal killings were exchanged between the two religious factions raising the sceptre of civil war in the country.
Wednesday’s attack was similar to a bombing last Friday when three suicide bombers, two dressed as women, blew themselves up near a Shia mosque in Baghdad after weekly prayers.
That bombing killed 79 people and was labelled the deadliest attack this year on Iraq’s dominant majority Shiite community.
The latest attack comes after the Iraqi parliament announced it would convene next week in a bid to break months of deadlock on the formation of a new government, largely blocked by disputes over the fate of Shiite Prime Minister Ibrahim Jaafari.
But a positive sign came from speaker Adnan Pachachi, telling reporters that parliament was set to meet April 17, marking only the second time the body has met in the four months since a landmark election in December.
“There are signs that there will be agreement on all problems concerning formation of the government,” Mr Pachachi said.
The new parliament was inaugurated on March 16 but was immediately adjourned as there was little prospect of a deal on a government of national unity.
A major point of contention is the candidacy of Mr Jaafari, who has continues to defy mounting pressure even from some Shiite allies to withdraw.
Kurds and Sunni Arabs parliamentarians have called for his resignation pointing to Mr Jaafari’s inability to curb sectarian violence.