The pair were seen "holding hands and kissing" at West Hollywood, reports Us Weekly.
An insider claimed: "They're seeing where it goes. They liked each other, but fought a lot."
"They're taking it slowly this time," another source said.
Roberts and Overstreet, who began dating in early 2011, ended their nine-month relationship in January.
Prior to their split, Roberts was said to have "repeatedly ditched" the Glee actor. A source alleged that Roberts was "pretty difficult to be in a relationship with".
Meanwhile, another insider said that Overstreet was "controlling" and always wanted to know of Roberts's whereabouts.
Watch a clip from Glee below: