A theoretical model for the galvanostatic chronopotentiometry on a randomly rough electrode is developed for the diffusion controlled mass transport. The proposed model addresses the influence of various morphological characteristics of roughness on the transition time, interfacial concentration and potential transients. The potential transient and transition time of rough electrode is expressed in terms of average interfacial concentration. Expression for the average surface concentration is obtained in terms of the power spectrum of roughness while detailed analysis of simulated chronopotentiograms is performed for the finite fractal model. Power spectrum of finite fractal roughness is characterized through three controlling parameters of roughness, viz. fractal dimension (DH), lower cutoff length scale of fractality (t) and topothesy length (2,), significantly influence the chronopotentiometric response. Theoretical result show that the transition time at a centered random or pitted surface decreases with increase in their roughness. Experimental data on rough Pt electrode corroborate this observation and quantitative agreement over all time scale is achieved after inclusion of correction for the electric double layer and ohmic contributions.