Mohammed Salem al-Ghabban submitted his resignation at a press conference Tuesday in Baghdad, citing a lack of "coordination among security systems" as the reason for his departure.
His resignation was predictable fallout from the immense blast early Sunday in the capital's Karrada neighborhood
, where about 250 people were killed and at least 200 injured.
As grieving families buried victims Tuesday, Iraq's government scrambled to mollify public anger over what was seen as a critical failure of the country's security services.
In an embarrassing admission, the government has had to order security personnel to stop using bogus bomb detectors that, for years, have been widely known to be useless.
Retired Lt. Col. Rick Francona, a CNN military analyst, said Tuesday that the fallout to the massive security lapse could also see the delay of the government's long-awaited push to retake the ISIS stronghold of Mosul.
"(Iraq's government has) to reassess what they're doing," he said.
"The residents of Baghdad are more concerned about their own security rather than this eventual inevitable fall of Mosul. The Iraqi government will eventually go back and retake Mosul, but they have to secure Baghdad first."
The Sunni terror group, which has carved out a self-declared caliphate in parts of Iraq and Syria, has been losing territory, most recently in the Iraqi city of Falluja
The government has assured people that ridding Falluja -- about 65 kilometers (40 miles) west of Baghdad -- and the rest of Anbar province of the terror group would deliver improved security to the capital, but it hasn't been the case.
Instead, Baghdad has suffered the deadliest of a string of terror attacks across the world executed or inspired by ISIS during the Muslim holy month of Ramadan.
"ISIS is going to continue to do this, because this is success for them," Francona said.