The differences noticed in the order of preference for alkali metal cations through the channels of Prussian blue surface modified electrodes during redox reaction in aqueous versus acetonitrile media are presented. Since intercalation/deintercalation processes by alkali metal cations like K+, Na+, Li+, etc., help in deciding the efficacy of the PB film in device fabrications, the associated columbic charges and diffusion coefficient values computed from chronoamperometric and chronocoulometric studies are reported.