The pair split late last year, with Gomez recently admitting that she is "having a good time" being single.
TMZ reports that Gomez was seen spending time with Bieber on Saturday (February 2), returning home late at night.
Sources claimed that this is the first time the pair have seen each other in a month, though it is unclear where their relationship currently stands.
The 20-year-old Gomez is set to appear in Harmony Korine's Spring Breakers later this year.
Bieber, meanwhile, will host an upcoming episode of Saturday Night Live this month.
Watch Justin Bieber's video for 'Boyfriend' below:
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