A second-round pick (61st overall) from Alabama, Lacy was a key performer in the Packers' offense, particularly when star quarterback Aaron Rodgers was sidelined for seven games. He rushed for 1,178 yards on 284 carries (4.1 average), with 11 touchdowns. He also had 35 receptions.
That was good enough for 35 votes from a nationwide panel of 50 media members who regularly cover the league in balloting announced Saturday night.
The first Packer to win the award since John Brockington in 1971, Lacy beat out San Diego wide receiver Keenan Allen, who received 12 votes.
He is the first running back to take the offensive rookie honors since Adrian Peterson in 2007.