The 23-year-old actress spent three hours with Pattinson, 27, at his Beverly Hills home on Wednesday, reports femalefirst.co.uk.
The duo had parted ways in May after a four-year relationship.
A source told usmagazine.com that the former couple drove off in different directions when they realised they had been identified by photographers and Stewart went back to her property alone.
Stewart and Pattinson were last rumoured to have spent time together in August. A source at that time had said that they would reunite as they had a "very intense conversation" at Stewart's house.
Meanwhile, Pattinson was rumoured to be dating Dylan Penn and Stewart was linked to actor Lane Garrison.
--IANS (Posted on 01-11-2013)