According to People, Sandra Bullock's ex and the LA Ink star were seen dining together and holding hands in Las Vegas on Saturday.
The pair were seen sitting close to each other in an oversized booth at the Palms Casino Resort's N9NE.
Representatives for James and Kat Von D have not commented on the report.
Bullock and James finalised their divorce in June.
Kat Von D previously dated Motley Crue bass player Nikki Sixx.