Amukamara was New York's first-round choice, and 19th selection overall, in this year's draft. The former Nebraska defensive back missed the first five Giants practices but was in camp Friday to sign the contract.
Amukamara was a unanimous all-America pick last season after his assigned receivers caught just 18 passes over 14 games. He broke up 13 passes and had 59 tackles and a sack. He was the Big 12 defensive player of the year as Nebraska played its final season in that league.
The Giants also said they signed rookie free agent cornerback Darnell Burks from Fort Valley State (Ga.). Cornerback Bruce Johnson, a third-year pro who suffered an Achilles tendon injury Thursday, was waived Friday.