The surface change of a Pd electrode developed by plastic deformation due to the phase transformation of alpha -PdH to beta -PdH has been characterised by fractal geometry. The beta -PdH phase formed in the matrix electrode of alpha -PdH phase causes the plastic deformation of the electrode and hence increases the surface roughness as well as the surface area. The fractal dimension of the Pd electrode surface modified by the plastic deformation was determined from the diffusion-limited peak current density during linear sweep voltammetric measurements. The surface fractal dimension obtained is increased from 1.97 to 2.09 with increasing fraction of beta -PdH phase in the matrix electrode from zero to unity.