Analysis of the coulostatic pulse technique, as applied to a redox electrode with two consecutive charge-transfer steps, Red-e(-) = X and X-e(-) = Ox, under conditions of non-stationary linear semi-infinite diffusion of the reagents Red, Ox and the intermediate X has been carried out. Relaxation equations for the linear current density-overpotential region and for different excitations (coulostatic pulse of a charge, trapezoidal and triangular pulses of current) have been derived in analytical form. Cases of the relaxation processes controlled by (a) consecutive charge-transfer and diffusion simultaneously and (b) pure charge-transfer kinetics have been considered. Simple analytical approximations of the relaxation equations have been obtained for limiting cases. These approximations can be used for the classical graphical analysis of experimental data to determine the kinetic parameters of partial charge-transfer steps. It is shown that the relaxation process immediately after coulostatic excitation is controlled by the fastest elementary charge-transfer step, and its kinetics can be determined from the initial portion of the transient decay curve.