The deal also has a player option that would bring his earnings to $32 million. There also is a club option for 2014 that could take it to $43 million.
The deal helped spark a pitcher to sign a similar contract. The Reds picked up righty Bronson Arroyo's $11.5 million option last month, and on Friday they added two more years that would bring his total to $35 million over three seasons.
The Rockies are counting on De La Rosa to continue the career upswing that began when he joined the team in a 2008 trade with the Royals.
De La Rosa's .249 batting average against is second lowest in club history for a starter, behind ace Ubaldo Jimenez's .227. He also ranks seventh in strikeouts with 434 and eighth in wins with 34.
De La Rosa -- whose 8.95 strikeouts per nine innings since he joined the club in 2008 rank tops all-time among Rockies starters -- slots in behind Jimenez, with righty Aaron Cook behind them. Right-hander Jhoulys Chacin, a potential ace, follows them. Righty Jason Hammel fills the rotation, although he could get a challenge from right-hander Felipe Paulino, recently acquired from the Astros, and righty prospect Esmil Rogers and lefty non-roster invitee Eric Stults.
The Rockies also are looking to re-sign one-time ace Jeff Francis after not picking up his 2011 option. The Mets, Pirates, Mariners, Astros and Brewers also have been identified as possible suitors for Francis.
Thomas Harding is a reporter for MLB.com. Read his blog, Hardball in the Rockies, and follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.