Abstract: The heteroatom substituted zeolite BY was synthesized in the process of hydrothermal synthesis of zeolite Y with some aluminium source substituted by boron source. The crystalline structure, surface acidity and catalytic properties of zeolite BY were characterized by Xray diffraction (XRD), infrared spectroscopy (IR), nuclear magnetic resonance (NMR), pyridineIR and microreaction activity test (MAT). The results showed that boron was incorporated into the framework of zeolite Y and the crystallinity of zeolite BY with an appropriate amount of boron incorporated was improved. The Bronsted acid sites were increased and subsequently the Lewis acid sites were decreased with the introduction of boron. The catalytic activity of zeolite BY for cracking and hydrogen transfer reaction was enhanced, the olefin in the cracking gasoline was decreased and the aromatic hydrocarbons were increased. Thus BY zeolite is an ideal active component for the olefinreducing FCC catalyst.