The midfielder, who had been linked with Dundee United, has instead agreed terms with the Easter Road club and is due to be unveiled this afternoon.
A former Aston Villa youth player, he also played for Cheltenham Town and Cambridge United before joining St Mirren in November and helping to kick-start their season after an 11-game winless run.
During his spell in Paisley, he made 30 appearances for Jim Goodwin’s side as they progressed to the semi-final stage of both the League and Scottish Cup. They also narrowly missed out on a top six spot when the league split and had to settle for seventh place finish.
The 22-year-old Irishman had been offered a new deal by the Buddies but, having been courted by United, he looked set to move to Tannadice before Hibs swooped.
The hard-working midfielder is valued for his use of the ball, accurately picking out passes and pulling strings in the middle of the park and he is able to sit deep and cover the back line, but he was also able to get on the scoresheet for St Mirren last term.
Hibs boss Jack Ross is a fan of picking up hungry young players on the way up.
Doyle-Hayes is expected to join Hibs on their pre-season training camp as they gear up for their first European tie, on July 22, and the return of league action at the beginning of August.