Diffusion problems on coplanar and elevated interdigitated microarray band electrodes (IDAs) were studied by the finite analytic numerical method (FAM). Chronoamperometric curves and steady-state current-potential curves for both coplanar and elevated IDAs were simulated for diffusion controlled and quasi-reversible systems. The simulated results for coplanar IDAs were compared with those available in the literature, and found to be in good agreement. The influence of the geometric parameters (electrode height h(e), ratio of electrode width w(e) and gap width w(g)) of the elevated IDAs were also investigated. The computing time necessary is much less compared with results in the literature.