PURPOSE: To prevent intrusion of a liquid from prepass processing liquid onto a toner developer and to suppress the decrease in the density of said developer by making the part where the toner density is low and the part where said density is high in the toner developer of the same liquid and performing the prepass processing in the part where the toner density is low.

CONSTITUTION: The 1st passage formed of a cathode plate 12 and an anode plate 13 and the 2nd passage formed of two sheets of developing electrodes 14, 15 are provided within the same vessel contg. a liquid toner developer 16. DC of a voltage E is impressed from a power source E to both electrodes 12, 13 by closing a switch S. If a toner developer ELP contg. the toner particles electrified to positive is used as the developer 16, the toner particles migrate to the cathode 12 side and the toner particles hardly exist near the anode 13. A photographic film which is exposed with an image by the developer ELP is passed between conveying rollers 11-a and is introduced by conveying rollers 11-b into the 2nd passage where the film is subjected to toner development. The development film is transferred into a fixing stage. The intrusion of the liquid from the prepass processing liquid is thus prevented and the photosensitive body is processed without decreasing the density of the toner developer.