Former Wales skipper Sam Warburton, who led the Lions to victory in Australia in 2013 and to a drawn series with New Zealand in 2017, says being captain of the party would "just suit" Itoje.
"I was so impressed with him in 2017," Warburton told BBC Sport.
"I would follow him into battle."
Alun Wyn Jones, who captained Wales to the Six Nations title and is targeting his fourth tour, is the heavy favourite to lead the Lions against the Springboks.
"Don't get me wrong, if Alun Wyn was captain I wouldn't bat an eyelid," Warburton added.
"Of course he would be a great captain. But you don't want to put too much pressure on someone, particularly when they are 35, to make the Test team."
Warburton says Itoje is a "shoo-in" to be in the starting XV for the three-Test series against the world champions, which tips the balance in the Englishman's favour.
"I think Maro, James Ryan and Alun Wyn, their ceiling is the highest out of the second rows," Warburton explained.
"And out of the three, I think Maro is a shoo-in, and I think James Ryan and Alun Wyn will battle it out for the number five shirt.
"I know people will think [Itoje] is under-cooked, and hasn't played much, and gave away a load of penalties [in the Six Nations], but he still had a big influence on those games.