Bruce - now with Sunderland - is back at St Andrew's for the first time since leaving in 2007 and is bound to get a warm welcome from the Brum supporters.
McLeish said: "Steve should get a nice polite clap when he's walking down the touchline. But when he reaches the dugout, the supporters should be right on his back. I'd like them to be relentless and get back to the kind of fans Steve inherited when he came to Birmingham.
"They were notorious for their vociferous support of the home team and how they unsettled the away team.
"The fans have been doom and gloom for a wee while. It's time they got back to the support they are notorious for."