Electroless deposited Pd coats have been prepared on Nb-Ni-Ti alloy membranes and glass substrates, XRD, DSC, SEM and EDX analysis were employed to determine the phase compositions, thermal stabilities and surface morphology of Pd deposited coats in this paper. It revealed that prepared Pd coat appeared to be a particle-deposited surface image with amorphous microstructure, consisting of numerous spherical particles (1 μm or so) arranged in single-layer form, the content of P in the coats is about 3 wt%-4 wt%. Such coat can keep its original appearance, but slight increase of particle size, strong intensity of Pd phase and Pd6P have been observed after heat treatment at 675 K. Hydrogen diffusion coefficient of Nb-Ni-Ti alloy membranes with original amorphous Pd coat is quite higher than that of samples without Pd coat, as well as that of samples with Pd coat after heat treatment at 675 K, indicating that prepared Pd coat has good catalytic effect on hydrogen permeation of Nb-Ni-Ti alloy membranes.