Harper signed a contract with the Jets on Tuesday, Ethan Greenberg of the Jets' official site reports.
Harper was released by the 49ers at the beginning of the month after one season with the team. In nine games with the 49ers, the 23-year-old recorded 13 receptions for 133 yards. He'll now have a chance to compete with a whole host of wideouts vying for spots behind starters Eric Decker and Quincy Enunwa.