Production of lighter hydrocarbons were maximized by steam-assisted catalytic cracking of heavy oil over silane treated Beta catalysts. Steaming environment may cause dealumination of zeolites and affect the stability of zeolites. Herein, we improved the hydrophobicity and stability of the Beta zeolite catalyst (SiO2/Al2O3 = 150) by modifying its surface using triphenyl silane through vapor phase deposition technique. Parent Beta and silane treated Beta catalysts were tested in fixed-bed flow reactor for steamassisted catalytic cracking of atmospheric residue. It was found that the modified Beta catalyst retained its crystallinity and phase purity after reaction. Moreover, coke formation was also reduced significantly over silane treated Beta catalysts. This indicates the increase in the stability of catalysts. Furthermore, the yields of gases, gasoline (C-7-C-13) and gas oil (C-14-C-20) over a silane treated Beta zeolite catalyst were 11.6 mol%, 55.7 mol% and 3.7 mol% respectively for 2 h reaction time. (C) 2015 Elsevier Ltd. All rights reserved.