In this study, NiK/yCe(x)Zr(1-x)O(2)-macroporous Al2O3 catalysts (y = 0,10,20, and 30; x = 0.73-0.92) were synthesized by dispersing different amounts of CexZr1-xO2 phase onto macroporous gamma-Al2O3 as supports, and then subsequently impregnating Ni and K into the supports, which possessed advantageous properties, such as a high surface area, ordered macropores and high oxygen storage capacity. Moreover, the introduction,of Ni and K metals into these supports created more oxygen vacancies in them. We applied these catalysts to the cracking of vacuum residue with steam. It was found that the variation of the liquid yield with the amount of CexZr1-xO2 phase showed a volcano pattern. The macropores in the supports played an important role in enhancing the diffusion of large molecules to the active sites, while the high oxygen storage capacity over the CexZr1-xO2 phase improved, the oxidative cracking rate, thereby increasing the lighter oil fraction from the vacuum residue. (C) 2016 Elsevier B.V. All rights reserved.