Ruiz was singled out by fans who voiced their displeasure as Fulham slumped to 16th place and two points away from the relegation zone.
Jol said: "The Premier League is a tough world. If you do well the people will praise you and if you don't they will boo you. He's quite strong, he's not a pussycat. It will affect him personally but I don't think it will affect his game."
Whether Jol risks Ruiz depends on whether the Costa Rican attacking midfielder has sufficiently recovered from a niggling back problem which has troubled him for the past few weeks and saw him miss a training session in midweek.
But Jol refuses to panic as the pressure grows on himself and his team.
"If they (the fans) are disappointed I can understand that," Jol said. "The only disappointing thing was with Ruiz.
"As long as we don't have the results they can do it (boo) with me, but hopefully they will support the team. We are not in the best of situations, but we are not in the worst."
Jol also has a doubt about Norwegian central defender Brede Hangeland, who has been suffering from a sciatic nerve problem but whose experience could be crucial against the Liverpool strikeforce of Luis Suarez and Daniel Sturridge.
Jol knows Suarez well, having managed him at Ajax where he made the Uruguayan striker his captain.
He has tried to pass on inside knowledge to his defenders but acknowledged the talent of Suarez is difficult to shackle.
Jol said: "Suarez is one of the best in the world and he will prove that. He will score a lot of goals. He would have been top scorer last year if he had not been suspended.
"Sturridge has also had a big impact since he went to Liverpool. They are very good going forward with these top players up front.
"Maybe you could stretch your imagination a bit and say they could be title contenders. They are strong and they will be going for a top four spot this year."
Fulham will be without right-back Sascha Riether, who begins his three-match suspension after being found guilty of violent conduct by the Football Association for stamping on Manchester United's Adnan Januzaj.
Meanwhile, Jol admits he would allow reserve goalkeeper David Stockdale to leave on loan if he had back-up for number one Maarten Stekelenburg.
Jol said: "If I had another very good goalkeeper I would send him (Stockdale) on loan. Neil Etheridge (Fulham's third choice goalkeeper) hasn't got the experience yet. He has never played in the Premier League.
"Goalkeepers live by experience. Neil is one of the 'keepers who should go on loan and get 50 or 75 games under his belt and then be a good goalkeeper because he is talented.
"Stockdale is different. He's already played a lot of games in the Premier League and he was fine at the start of the season. But he is ambitious and wants to be in goal and I can understand that."