The Terminator actor split with his wife of 25 years back in May after he was alleged to have fathered a love child with one of their staff.
The two have reunited several times since, most recently at a lunch to celebrate his 64th birthday in July.
In photos published by the Daily Mail, Schwarzenegger can be seen sitting outside a cafe in the US state of Idaho wearing a gold band on his left finger.
The ex-California Governor continued to wear his wedding ring in the immediate aftermath of the split, but has been spotted without it in the last few months.
The images follow a report earlier this week claiming that Shriver is beginning to reconsider her divorce.