Snee, 26, will earn nearly $24 million in the first three years of the deal, agent Tony Agnone said.
The extension will keep the right guard under contract with the Super Bowl champions through 2014.
Since beating the New England Patriots for the NFL title in February, the Giants have locked up three starters on the offensive line. Left tackle David Diehl got a two-year extension last month that will keep him under contract through 2013 and pay him $31 million. Left guard Rich Seubert also got a new contract through 2013.
Right tackle Kareem McKenzie and center Shaun O'Hara are under contract through 2012.
"Chris thought re-signing everyone was important," Agnone said in a telephone interview with The Associated Press. "They can have a cohesive unit for a while now."
The signing will also keep the family happy. Snee is the son-in-law of coach Tom Coughlin. The Giants rewarded the coach after the Super Bowl with a four-year contract worth $21 million.
"I am just happy to have it done before the season and really just have peace of mind and not worry about it and go out and play," Snee said. "I had faith that it would be done."
A former second-round draft pick, Snee has started all 59 regular-season and six postseason games that he has played for the Giants. The former Boston College product has started 48 consecutive regular-season games. He missed the final five games of his rookie season because of an inflamed gland under his jaw.
"We are very pleased to get Chris extended," general manager Jerry Reese said. "He has been a tremendous player and person for us since day one. It's also very important to keep our offensive line intact."
The Giants scored 373 points, their fifth-highest total in franchise history, last season. New York averaged 134.3 yards rushing, fourth best in the league.
The Giants also acquired guard Kurt Quarterman off waivers from the Atlanta Falcons. He spent most of last season on the Falcons' practice squad.
