Sunday’s statement identified the leader as the so-called Wali of Anbar, another name for ruler or governor. It gave only his nickname, Abu Mansour.
Three other militants were killed in the air strike carried out by the Iraqi Air Force in co-ordination with the Federal Intelligence and Investigation Agency, the statement said.
Handout pictures showed a damaged lorry in a desert area. Nearby lay a charred body, rifles and ammunition, and plastic bags full of oranges and cucumbers as well as biscuits.
The dead commander had been behind attacks against travellers in Iraq's Rutba area, on the main road linking Baghdad to Amman in Jordan, the statement said. He assumed different positions in Iraq and Syria.
The statement said: “ISIS terrorist gangs have lost one of the most important criminal leaders.”
It did not say when the strike was carried out.
In mid-2014, ISIS overran large parts of Iraq and Syria, declaring a “caliphate” in the two neighbouring countries.
Backed by a US-led international coalition, Iraq announced victory against ISIS in late 2017 after three years of gruelling fighting.
However, the terrorist group's cells continue to mount hit-and-run attacks, particularly in vast desert regions of northern and western Iraq near the border with Syria.
Marking the eighth anniversary of the ISIS onslaught Iraq last week, Prime Minister Mustafa Al Kadhimi praised the security forces for chasing down the militants.
"Today, security has prevailed and the borders are protected thanks to the efforts and sacrifices of our security forces," Mr Al Kadhimi said during the weekly Cabinet meeting on Tuesday.
"And I personally supervise the daily security and military operations to chase down the terrorist ISIS remnants," he said.
Earlier this month, the prime minister acknowledged that "there are attempts by terrorist groups to kill civilians to gain a foothold or to be in the news and there are dozens of operations against them on daily basis."
"Few months ago, the Counter-Terrorism Service led an operation in Mosul and killed 45 militants," he said, without giving more details.
Using the dust storms that have hit Iraq in recent months as cover, the group has intensified attacks on security forces and civilians in the country’s north and west.
Last month, it claimed responsibility for two attacks on villagers in remote areas in northern and eastern Iraq, killing at least 12 and leaving several others wounded.
Iraqi security forces have been launching almost daily air strikes or small-scale military operations against ISIS in remote areas.
There is no specific number for how many ISIS militants are active in Iraq, but counter-terrorism officials say there are thousands, who operate as separate cells, carrying out quick attacks on selected targets.