Crawford hit .296 and led the American League in triples (19) and stolen bases (59) last season. He also hit 11 homers, drove in 55 runs and scored 104.
"This is one of the happiest days of my life," Crawford said after the signing was announced.
"The future of this organization is exciting, and it is great knowing that I am going to be a part of it. I am grateful the Devil Rays have the confidence in me to make such a long-term commitment."
The 23-year-old Crawford, Tampa Bay's leadoff hitter, has played two seasons in the major leagues. He made the American League All-Star Team in 2004.
Devil Rays Manager Lou Pinella said Crawford's long-term deal, in the $30 million range, "should send a clear message to our young players that if you go out and play hard and do the job you will be rewarded."