There is provided a catalyst composition having improved hydrothermal stability for the catalytic cracking of a hydrocarbon feedstock to selectively produce propylene. The catalyst composition comprises a first crystalline molecular sieve selected from the group consisting of IM-5, MWW, ITH, FER, MFS, AEL, and AFO and an effective amount of a stabilization metal (copper, zirconium, or mixtures thereof) exchanged into the molecular sieve. The catalyst finds application in the cracking of naphtha and heavy hydrocarbon feedstocks. When used in the catalytic cracking of heavier hydrocarbon feedstocks, the catalyst composition preferably comprises a second molecular sieve having a pore size that is greater than the pore size of the first molecular sieve. The process is carried out by contacting a feedstock containing hydrocarbons having at least 4 carbon atoms is contacted, under catalytic cracking conditions, with the catalyst composition.