The team also agreed to a $3.5 million, one-year deal with outfielder Angel Pagan.
The deal will guarantee Dickey $7.8 million. He otherwise would have been eligible for free agency next offseason. He gets a $1 million signing bonus, $2.25 million this year and $4.25 million in 2012 under Monday's agreement. The Mets have a $5 million option for 2013 with a $300,000 buyout.
Pagan, 29, hit .290 with 11 homers and 69 RBIs, becoming the starting center fielder while Carlos Beltran was sidelined.
Dickey emerged as a finalist for NL Comeback Player of the Year after resurrecting his career with the Mets last season at age 35.
The payday is particularly rewarding considering Dickey's personal history.
"A lot of you guys know where I have come from, and now where I am," Dickey said. "And it's been a long road to say the least. ... Things are going to get better. I feel like I'm really getting to a place where I can know what I have to offer and offer it consistently. It's a nice place to be."
Originally the 18th overall pick in the 1996 draft by the Texas Rangers, Dickey had his $810,000 signing bonus reduced to $75,000 because doctors discovered he lacked the ulna collateral ligament in his right elbow.
The first cut in spring training last year after signing on a minor league deal with the Mets, Dickey was promoted on May 19. He ultimately went 11-9 with a 2.84 ERA in 27 appearances (26 starts) while setting career highs in wins, starts, innings, strikeouts and complete games.
Dickey was a conventional pitcher who toiled with a knuckleball earlier in his career, but shoulder woes that took away his velocity prompted him to reinvent himself and rely on the pitch in 2005. He reached out during that time period to Tim Wakefield for advice.
Dickey said last season that when he was learning the knuckleball in 2005, '06 and '07, he studied a lot of film and learned pretty quickly he had to develop his own style.
"If I spend a lot of time trying to be Tim Wakefield, I'm going to lose who I am," he said. "And that spells bad news."
As for Wakefield's continued input, Dickey said: "We talk a different language when we talk to each other -- a lot differently than a pitching coach would address a traditional pitcher. He's done everything from look at my tapes to watch my bullpens."
As Dickey noted, all knuckleballers are not created the same.
"We have two different styles," he said. "I still have more arm strength than he does, just because I was a conventional pitcher before I became a knuckleballer. He was a position player. I still have a little bit of a fastball. And my knuckleball is probably on average about six or seven miles per hour harder than his.
"That doesn't make it better. That's just the way it is. If you ask somebody that was intimate with what a knuckleball does and is, I'd say they would probably liken me more to Joe Niekro, Phil's brother -- a guy who threw kind of hard and mixed in other pitches as well from time to time. But if we're throwing it good, then it's good. It comes out with no rotation and then it's hard to hit."
"R.A. really had an outstanding season," Mets general manager Sandy Alderson said. "I think part of our confidence for the future comes certainly from that platform, if you will. Also I think it comes from our own view as well as opinions of others that the knuckleball is a unique talent and something that can play very well later in a pitcher's career.
"In this particular case, a year or potentially two years of free agency are involved. So this was an opportune time for us to make a commitment and get something ... in return. Yes, we want to maintain flexibility going into 2012, but our decision-making with respect to next year and so forth we have to begin to consider now. R.A. is one of those guys we felt we could commit to."
The Mets have no more players up for arbitration.