PURPOSE: To obtain a printing plate processing device with which automatic washing is possible.

CONSTITUTION: An eluting section 26 is provided with pipings 212, 214, 216 for washing along the upper circumferential edges of an eluting tank 104, a washing tank 106 and a gum liquid tank 108. Washing water is supplied by operation of a washing water pump 210 to these pipings for washing. The supplied washing water is gushed out of the pipings for washing along the respective tank walls, by which the tank walls are washed. The eluate, washing water and gum liquid in the eluting tank 104, the washing tank 106 and the gum liquid tank 108 are discharged as waste liquids from solenoid valves 174B, 180B, 196C. The washing water supplied by a washing water pump 210 is automatically drained from solenoid valves 174A, 180A, 196A.