Provided are a modular processing unit that is standardizable, capable of enhancing production efficiency, and is also flexibly customizable, and a fully automatic gravure cylinder manufacturing system using the modular processing unit. The modular processing unit includes a pair of frame members provided upright so as to face each other, a first processing module including a first processing bath module, a first beam module provided horizontal to a floor, and a first chuck module, and a second processing module including a second processing bath module, a second beam module provided horizontal to the floor, and a second chuck module. The modular processing unit has multi-stage structure with at least the first processing module and the second processing module being assembled onto the frame members.