The invention relates to a power distribution control center device and a designing and installing method, in particular to a modularization box type integral integrated electric control device for a fuel gas power plant and an installing method of the modularization box type integral integrated electric control device. The modularization box type integral integrated electric control device is characterized in that a fixed type electric control device with an electric control functional column screen cabinet which needs fixed building space to be installed is changed into the modularization box type integral integrated electric control device which is capable of being transported, detached and spliced and is provided with detachable walls; modularization design is adopted in each box, the boxes can be integrally hoisted, jacked and moved, each box and all systems in the box can be independently and integrally transported to the field and installed on the outdoor civil engineering foundation, and the walls of each box are designed to be detachable, and can be dismounted or mounted conveniently in the factory or the power plant field. The modularization box type integral integrated electric control device has the advantages that installing is convenient, the adaptability is high, time and labor are saved, the wiring error rate is greatly reduced, building cost is reduced, and the construction period is shortened.