The selective light reflection and turbidimetric property of concentrated aqueous solutions of (hydroxypropyl)cellulose (HPC), originating from their cholesteric mesophase structure and LCST-type phase behavior, respectively, are much affected by coexistence of inorganic salts therein. This is ascribed to a strong dependence of both cholesteric helical pitch (P) and cloud point (T-c) of the aqueous cellulosic solutions on the sort and concentration of the additive salts. By virtue of electrophoretic motility of the coexistent salt ions as P and/or T-c shifter, the dynamic variation in cholesteric coloration and/or optical turbidity of the HPC solutions was realized under the action of a relatively weak electromotive force to electrodes in contact with their layered sample. It was reasonably taken that the electrical stimulation allowed the ion particles to migrate and localize in this lyotropic system, resulting in occurrence of a certain degree of gradient in magnitude of P and/or T-c in response to the uneven ionic distribution. To make clearer the mechanism of the novel electrooptical function, discussion took into consideration a storage effect of electric charge in the solution samples, detectable as a remaining potential difference after cessation of the application of the electric field.