Dembele's future has been the subject of intense speculation this summer, with the likes of Manchester United, Tottenham Hotspur and Real Madrid reportedly interested in the Belgium international.
Despite Dembele's agent confirming that there had been contact with Madrid, Jol denied that the Spanish giants had made an offer, and claimed that the one offer they had received for the player was too low.
"I spoke to his agent and I said to him it's not the cleverest thing to do, to speak about players," said Jol.
"There was no offer on the table [from Madrid] and hopefully the situation will stay as it is. Hopefully Dembele will stay here.
"There was one low bid from one Premier League club, very low. Moussa is quite happy here. He wants to play here and if something happens, we will have to wait."
Fulham will host Norwich City in tomorrow's Premier League opener.