Zimmerman was seen walking out of the jail smiling, then getting into a car.
His bond was set at $9,000 earlier in the day.
The judge ordered that Zimmerman not possess guns. He was ordered to stay away from the girlfriend's house and wear a monitoring device.
Zimmerman has been charged with aggravated assault, a third-degree felony. He was also charged with battery and criminal mischief, both misdemeanors.
Zimmerman was taken into custody Monday after girlfriend Samantha Scheibe told deputies he pointed a shotgun at her. In a 911 call, Zimmerman denied pointing a gun at Scheibe.
The 30-year-old former neighborhood watch volunteer was acquitted earlier this year of criminal charges in the fatal shooting of Trayvon Martin.