The pair replace Jimmy Calderwood, Jimmy Nicholl and Sandy Clark, who left Pittodrie last month.
Former Toon Star Named As Manager!
McGhee was part of the Dons side which won the European Cup Winners' Cup in 1983 with a 2-1 win over Real Madrid in Gothenburg.
Dons director of football Willie Miller: "The board was unanimous in the choice of Mark for our new manager, as everyone knows, these situations can be extremely delicate and you have to allow for all eventualities.
"That said, we're delighted Mark and Scott have agreed to join us and with the return of European football next month, these are exciting times here at Pittodrie.
"Mark is well known to most Aberdeen supporters and of course, having been here as a player, he also knows what the club means to them and he's itching to get started."
The new management team's first official day in charge will be Wednesday July 1 when the players report for pre-season training.
*1977/91 M.E.McGhee 99/13 36
Two spells at Newcastle and they couldn't possibly have been so different. He came from Morton for £150,000 and looked as though he had the skill to make it, but always failed to deliver. He lacked strength and pace. But he went to Aberdeen and became a superstar. Capped by Scotland, he won Scottish Championships and Scottish Cups with both Aberdeen and Celtic. As well as European Cup Winners Cup medal with Aberdeen. Signed for Newcastle for £200,000 and hit it off with Micky Quinn straight away.