The mass transport behavior of Prussian blue (PB) films in acetonitrile (AN) and propylene carbonate (PC) solutions has been revealed using the cyclic electrochemical quartz crystal microbalance (EQCM) technique and the electrochemical/electrogravimetric impedance technique. It was found that cation transport is dominant during the redox reaction of PB films in AN solutions, whereas anion as well as cation takes part in ion transport in PC solutions. It was also found that anion transport is greater in a Li+-containing solution than in a Na+-containing solution. These results are discussed in terms of zeolitic structure of PB films and ionic mobility. Moreover, using the electromechanical impedance technique, it was shown that the morphological change during the redox reaction of PB films is not significant.