The left-hander will follow right-hander Jeremy Guthrie in the rotation and precede right-handers Juan Nicasio and Jhoulys Chacin.
With an off day on April 10, the Rockies will open the season with a four-man rotation. Left-hander Drew Pomeranz will join the rotation and make his first start April 15.
Pomeranz was optioned to Triple-A on Friday.
Moyer missed the 2011 season after undergoing Tommy John surgery. By returning to the majors, he will be the active leader in victories (267), innings (4,020) and starts (628). In his last season, he went 9-9 with a 4.84 ERA with the Philadelphia Phillies in 2010.