The Germany international has been linked with clubs such as Juventus, Inter, Bayern Munich and Real Madrid in the past few months, but the Gelsenkirchen side are determined to hold on to the 19-year-old.
"There is no exit clause and we have no intention of selling Julian at the end of this season. He is feeling very well at the club and is the face of Schalke," Heldt was quoted as saying by Bild.
"What I would say if a 100 million euros offer came in tomorrow? You can't blame Julian for having the desire to play at one of his dream clubs in Spain at some point. If Barcelona or Madrid were to offer 100m euro, we would look at things differently.
"Bayern? Where would he have to play at Bayern with all the players they already have ..."
Draxler has a contract with Schalke until the summer of 2016.