The Dutchman's future has been questioned in recent weeks following the Cottagers' disappointing start to the Premier League season.
Despite the team's poor form, Hayles believes that Jol should be given time by new owner Shahid Khan.
"They've had a horrendous start to the season, but it's still early days," he told The Mirror. "The new players haven't bedded in yet and need time to gel.
"Hopefully the new owner realises that and doesn't give him the chop.
"It hasn't been great, but I think it's important there isn't a knee-jerk reaction."
Fulham will be looking to end a winless run of five matches in the league on Saturday when they host Stoke City.