After managing Forest Green Rovers for just one victory in 18 games, which resulted in their relegation from League One, the 51-year-old quit the club in July.
Ferguson had entered management for the first time on his own at Forest Green.
Ferguson will succeed the fired Billy Dodds, and his appointment will be revealed at a press conference on Tuesday morning.
With just one point from six games, Caley Thistle sits in last place in the Scottish Championship.
After spending two seasons at Everton as a player, Ferguson returned to the Premier League team as a coach under fellow Scot David Moyes and later served as both assistant manager and caretaker manager twice.
He departed Goodison Park in July of last year, and in January, he was named the head coach of Forest Green.
The first game without Dodds for Caley Thistle director of football John Robertson’s team was a 1-0 loss to Dundee United on Saturday.
Dodds’ last game was a 1-0 loss to Raith Rovers at Kirkcaldy, and it was the second week in a row that a late goal had given Caley Thistle’s opponents a victory that propelled them to the Championship peak.
Ferguson, who began his career with Dundee United and later transferred to Rangers, scored 73 goals for Everton before going on to Newcastle, and he was given seven Scotland caps.
