The 21-year-old midfielder arrives at the Proact after an undisclosed deal was agreed between the two clubs.
Morsy explained why he decided to sign for the Spireites. "I know the ambition of the club and I want to be a part of it," he said. "I've known the manager for a number of years and I know his philosophy. That was a big factor in my decision to sign."
Paul Cook said: "He's a very tenacious central midfielder who can handle the ball and drive forward. He's got that little bit of devilment in him that we'll need to curb at times but good players have that.
"He's a good age and he comes in with a desire to get better. When we found out that he may be available, we moved heaven and earth to get him here."
Morsy, who spent nine years in the Wolverhampton Wanderers academy before being released as a 16-year-old, initially joined Port Vale 's youth set-up before being handed a professional contract in 2010.
He made 32 appearances last season, helping Vale win promotion to League One. In total, he scored four goals in 78 appearances during his spell at Vale Park.