Application of composite Pd based membranes represents a promising alternative for H2 purification. Here we propose the application of asymmetric Al2O3 hollow fibres as a support for Pd deposition. Hollow fibres were sintered at different T (1300 and 1400 C). Characterisations of the substrate showed that it presents the desired morphological structure, with finger-voids extending to almost 90% of the fibre, high porosity and suitable mechanical strength. The increase in the sintering temperatures increased the gas and water permeation through the substrate. For composite membranes formed by 1 Pd layer, the decrease in the substrate sintering T from 1400 to 1300 C increased the H2 permeation in 130%. For 2 Pd layers, this difference decreased to 21%, showing that the substrate influence is more evident in thinner Pd membranes. The obtained H2 flux was equal to 0.80 µmol m-2 s-1 (at 450 C and 180 kPa) and it is one of highest flux reported in the literature.