A series of MenAg0.3Mo0.5P0.3Oy (Me = Cu, Zn, Mn, W, Ce, Pr, Nd) and Ag0.3Mo0.5P0.3Ox catalysts were prepared. The addition of Ce to Ag0.3Mo0.5P0.3Ox catalysts improved the catalytic performance in selective oxidation of propane to acrolein, and Ce0.1Ag0.3Mo0.5P0.3Ox catalysts showed the highest acrolein selectivity (28.7%) and yield (4.4%). The physicochemical properties of Ag0.3Mo0.5P0.3Ox and CenAg0.3Mo0.5P0.3Ox (n = 0.1-0.5) catalysts have been comparatively characterized by BET, XRD, H-2-TPR, XPS, EPR and C3H8(C3H6)-TPD. Significant differences in physicochemical properties between Ag0.3Mo0.5P0.3Ox and Ce doped Ag0.3Mo0.5P0.3Ox catalysts have been observed, which is due to the formation of the redox cycle (Ce3+ + Mo6+ double left right arrow Ce4+ + Mo5+) in the CenAg0.3Mo0.5P0.3Oy catalyst. Such effect modified the reducibility, the concentration of Mo5+ the activation of propane and the transformation of possible intermediate propene to acroelin, which in return greatly influenced the catalytic performance of Ce doped Ag0.3Mo0.5P0.3Ox catalysts in selective oxidation of propane to acroelin. The proper addition of Ce to Ag0.3Mo0.5P0.3Ox catalyst improved the acrolein selectivity and yield. (C) 2003 Elsevier Science B.V. All rights reserved.