Iraqi forces had recaptured parts of Anbar University in May, shortly after losing the provincial capital to the jihadists, but later pulled back.
The university was retaken by elite forces from Iraq's Counter Terrorism Service (CTS), known as the "Golden Brigade".
"The Golden Brigade managed to liberate Anbar University with backing from the army as well as air support from the coalition and Iraqi aircraft," Brigadier General Abdelamir al-Khazraji, deputy commander of CTS forces in Anbar, said.
"The Iraqi flag is flying above the university presidency once again," he said.
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A statement from CTS said the Iraqi special forces had "inflicted heavy human and material losses to the enemy."
Ramadi Mayor Dalaf al-Kubaysi said: "What was left of the insurgents fled the area."
Anbar University's vast compound lies south of the main highway that circles Ramadi from the south.
Iraqi forces had retaken two neighbourhoods south of the highway and parts of the university campus days after the devastating May 17 fall of Ramadi.
The US-led coalition formed a year ago when IS threatened to conquer even larger swathes of Iraq has carried out thousands of strikes in support of Iraqi regular forces.
On July 24 alone, the US military said five air strikes in the Ramadi area destroyed IS positions and vehicles.
Iraqi forces had held on to parts of Ramadi for nearly 18 months before buckling in the face of a three-day jihadist blitz during which IS unleashed an unprecedented number of truck bombs.