The invention relates to an elastic corrugated pipe single-acting cylinder-driven mechanical gripper with a series-connection plate spring framework. The mechanical gripper consists of a palm and two flexible fingers or a palm and three flexible fingers. The flexible fingers are identical in structure. Each flexible finger consists of an elastic corrugated pipe single-acting cylinder and a series-connection plate spring. Dimensions of all plate springs connected in series are optimally designed according to grasping objects. The mechanical gripper is driven by the elastic corrugated pipe single-acting cylinder to generate a grasping force. The mechanical gripper applies to the grasping of fragile, brittle objects or the grasping of objects varying with shapes and dimensions. When connected with a robot body, the mechanical gripper particularly applies to the production and logistic fields for grasping, sorting and packing of foods, agriculture products and light industrial products.