UFC officials confirmed the 170-pound contest to ESPN.com on Sunday. The UFC 171 pay-per-view event will take place at American Airlines Center in Dallas.
Lombard (33-4-1) made a phenomenal welterweight debut in October, when he knocked out former title contender Nate Marquardt in less than two minutes.
A former middleweight champion in Bellator Fighting Championships, Lombard is 2-2 since signing with the UFC last year. Both wins have come via first-round knockout.
Shields (29-6-1) is coming off a split decision win over Demian Maia in the main event of UFC Fight Night 29.
The former Strikeforce middleweight champion is the No. 6 ranked welterweight in the world according to ESPN.com and hasn't suffered a loss since September 2011.