Hazard feels his fellow Belgium international is vital to City and that they are not the same team without the imposing central defender.
Kompany is struggling to recover from a groin problem which has sidelined him for the last three weeks for Sunday's showdown at Stamford Bridge.
Hazard admits if his compatriot is ruled out it will only improve Chelsea's chances of taking three points against their fellow Premier League title contenders.
"Kompany is really important for City because when he plays they win and when he doesn't play they lose, often," said Hazard.
"We know his quality and we're lucky to have him in the Belgium team. I prefer to play with players like that than against them."
Even if Kompany does make the game, Hazard feels Chelsea will have enough to beat City as he believes they are now starting to click under Jose Mourinho after a run of six wins in seven games.
"We are playing well at the moment and are in form," added Hazard. "We have won at Norwich, we won at home against Cardiff. We have got a good dynamic. I hope we can continue like this because this weekend we have another big, important match.
"Our role is to try to stay in the title race at the top of the table, win and carry on our way to the Arsenal game (on Tuesday, in the Capital One Cup)."
Hazard is enjoying playing under Mourinho and hopes to enjoy success at Chelsea under the guidance of the Portuguese coach.
"Jose brings his experience. He is a great coach. Us young players are impressed," continued Hazard.
"We are starting to know him. He is a good guy, someone who has his own ideas and who puts them in place.
"At the moment we are winning so all is well. He has won a lot of things before and I hope he wins more, that we'll be able to win trophies."
God I hope we beat them and their bloated squad of millionaire$ and show them how neither class nor titles can be bought. Ha. In all seriousness I can´t stand games against City. Either really dull or a loss. Thank God Tevez is gone. Very nervous about this one but I expect The Happy One will wheel out a very negative formation and the football will be dire, even if we´re on great form at the moment. Kompany is a huge miss.- danza