Catalytic partial oxidation (CPO) of n-butane under autothermal condition was studied over both incipient wetness (IW) and sol-gel (SG) prepared Pt/Al2O3 catalysts. These catalysts gave different results, with SG Pt/Al2O3 producing more H-2 and CO than IW Pt/Al2O3 under the same reaction conditions. The difference between these two may be attributed to the particle size of platinum: the observed Pt particle sizes on both freshly prepared and used SG Pt/Al2O3 was 50% smaller than those on IW Pt/Al2O3.