The electrochemical behavour of samarium in NaCl-KCl, KCl and CsCl melts have been studied in the temperature range 973–1173 K by different electrochemical methods. The diffusion coefficients (D) of Sm(III) and Sm(II) have been determined by linear sweep voltammetry, chronopotentiometry and chronoamperometry methods. The standard rate constants of charge transfer (k
s) for the Sm(III)/Sm(II) redox couple have been calculated on the basis of cyclic voltammetry data using Nicholson’s equation. The nature of working electrode on the standard rate constants of charge transfer for the Sm(III)/Sm(II) redox couple has been studied. The formal redox potentials E
*
Sm(III)/Sm(II) have been obtained in alkali chloride melts from the cyclic voltammetry data.