Derek McInnes' Dons side have had an impressive season and sit second in the Ladbrokes Premiership as they bounced back from a 3-0 home defeat to chasing Rangers with a 2-1 victory at St Johnstone on Saturday.
The Easter Road outfit, for their part, clinched the Championship title with a 3-0 home win over Queen of the South on the same day and now turn their attention to retaining the trophy won by the Leith club last season for the first time in 114 years.
McLeish won the Scottish Cup five times as an Aberdeen player before he went on to manage Hibs for almost three years, and speaking at a William Hill media event at Hampden Park, he warned the Dons of Neil Lennon's side.
"I think Hibs are dangerous," he said
"I don't think it is a formality for the Dons to just turn up and win and I see Derek McInnes is saying the same thing.
"Neil Lennon has great experience of these kinds of games.
"His team are on a high, having got promotion back to the Premiership and I see it as being a hard one to call.
"Derek bounced back after the Rangers game and the expectations will be that Aberdeen should win, should see Hibs off
But I think it is a hard one to call."
Source : PA