A control mechanism of a full-automatic multi-folded umbrella includes a bolt, a nut and a push rod disposed on the bolt and cooperating with the bolt. The push rod is connected with the nut and the top end of the middle sleeve. The lower end of the bolt is driven by a power source in the umbrella handle to turn clockwise or counterclockwise for the nut to be moved up and down along the bolt. The power source is controlled by a button on the umbrella handle. An umbrella opening/closing transformation ratio mechanism composed of two or three pull ropes is connected with each sleeve of a middle rod set as well as an upper nest and a lower nest to fold or unfold the umbrella.