A series of Pd/γ-Al2O3 catalysts with a designed loading of 1 wt % were prepared by the sol-gel method using boehmite (AlOOH) sols and various palladium compounds. These materials were developed for later use as inorganic membranes. The samples were calcined at 400 °C in flowing O2 to decompose the Pd complex and change the phase of the support to γ-Al2O3. H2 pulse chemisorption was used to determine the average Pd particle sizes, while particle size distributions were obtained from TEM micrographs. XRD was used to determine the crystallinity of the γ-Al2O3 support after extended treatments at 650 °C in O2 and H2 atmospheres. The physical properties of the support were studied using nitrogen adsorption-desorption at 77 K. Initial BET surface areas were about 350 m2/g. Pore size distributions were very narrow and centered at 3.6 nm, but broadened and became bimodal during the 650 °C treatments. An ion-exchanged sample prepared by traditional methods was used as a basis for comparison to the sol-gel samples.