Hardiman was placed on paid administrative leave from the anti-violence organization after he was accused of attacking his wife Alison Hardiman in their Hillside home Friday.
His contract expires on June 30 and the organization doesn't plan to renew it, according to a statement from Joshua Gryniewicz, CeaseFire's spokesman.
"Mr. Hardiman is no longer a representative of CeaseFire, its parent organization Cure Violence, or the University of Illinois at Chicago School of Public Health," Gryniewicz said.
Reached Monday night, Hardiman said he was "disappointed" in CeaseFire.
"The way CeaseFire handled this whole process was disrespectful and bogus," Hardiman told DNAinfo.com Chicago. "I am very disappointed in CeaseFire. You mean to tell me after I helped raise $6 million a year for them, they couldn't have enough respect for me to wait until the trial was over?"
Hardiman said he plans to start his own CeaseFire chapter.
"But let me get past this situation first," he said. "I am not going to let all the hard work I put into CeaseFire go to waste."
For now, Hardiman said he and his 18-year-old daughter are staying at a hotel in Westmont, but he hopes to move back to his Hillside home soon.
"I love my wife and in 13 years I have never put my hands on her and she knows it," he said.
On Monday, Chicago Police Supt. Garry McCarthy said that the department would continue to work with the group despite the allegations against Hardiman.
“The program is going to be evaluated on its success or failure and how effective it is — not this issue with Tio Hardiman, as far as I’m concerned,” McCarthy said.
Last year, the city awarded the organization a $1 million grant to help build its "violence interrupters" conflict mediation program in two police districts.
CeaseFire has taken some credit for the city's 43 percent decrease in homicides from January to April 2013 compared with the year before. In areas where "more than 100 trained violence interrupters and outreach workers are preventing and mediating conflicts," shootings have decreased by 40 percent over that period, Gryniewicz said.