The 67-year-old's current deal at the Allianz Arena expires at the end of this season, and although the former Real Madrid boss hinted that he may end his career, the Switzerland trainer thinks he will stay.
"He will renew his contract," Hitzfeld told Bild. "He makes every player feel like part of the whole group. That keeps the motivation high and forces competition.
"If you always play with the same 11 players, there is the danger that you get a two-class society. At Bayern, this is not the case and the coach is reliable. Heynckes looks very lively."
Hitzfeld also claimed former coach Louis van Gaal is still angry about his sacking in 2011, after the Dutchman claimed Uli Hoeness tried to force him out of the club.
"You can tell he is still mad that about being sacked by Bayern. It is always bad if a coach is resentful. I was not really sympathetic about that interview."