The actress was seen with the individual as she strolled through New York recently, her first public outing with a potential flame since she split from Sean Penn.
Johansson, who split from Ryan Reynolds in December 2010, was seen holding hands and wrapping her arms around the mystery male in the Big Apple.
The 27-year-old was beaming as she ran errands with the unidentified man, according to the Daily Mail.
The news comes after rumours surfaced that the Lost in Translation star is planning a move to London.
According to sources, she is desperate to avoid bumping into Reynolds with his new girlfriend, Gossip Girl star Blake Lively.
Watch the trailer for The Avengers, featuring Scarlett Johansson, below: