The Steelers released Watkins on Tuesday.
Watkins failed to secure his lone target while rushing once for six yards during Saturday's 9-3 preseason loss to the Bills.
Watkins is signing with the Steelers, Jeremy Fowler of ESPN.com reports.
Watkins did not record a reception in Monday's loss to the Seahawks.
Watkins was held without a catch or a target in Sunday's loss to the Cowboys.
Watkins returned from a hamstring injury Sunday against the Bills but did not receive a single target in the Eagles' overtime victory.
Watkins (hamstring) is active for Sunday's game against the Bills.
The Eagles activated Watkins (hamstring) off injured reserve Saturday.
The Eagles list Watkins (hamstring) as questionable to play Sunday against the Bills.
The Eagles designated Watkins (hamstring) for return from injured reserve Wednesday.