The painting depicts Florida state attorney Angela Corey, the special prosecutor who charged him with second-degree murder for the 2012 shooting death of 17-year-old Trayvon Martin. Zimmerman was acquitted in July.
The painting, titled "Angie," is a representation of a news photograph showing Corey holding he thumb and fingers together underneath the words "I have this much respect for the American judicial system."
Zimmerman sold a painting on eBay in December for $100,099.99.
Robert Zimmerman Jr., George's brother, posted a picture of the new painting on Twitter Wednesday, saying details of the sale of the work would be released Thursday.
The Associated Press contributed to this report.