The invention provides a pneumatic soft robot system and method for achieving lossless grabbing. The pneumatic soft robot has the advantages that a novel multi-cavity pneumatic soft robot is designed,the curvature is uniformly changed, and the stress concentration is weakened; and the advanced 3D printing Polyjet technology is adopted in the manufacturing process, the material rigidity of the soft robot can be controlled, reliability is high, integral forming is achieved, and repeated manufacturing is convenient. In order to achieve lossless grabbing, a laser distance measuring sensor is installed to detect the distance between the robot and a grabbed object, so that the movement speed of the robot is in a certain proportion to the distance, the soft and fragile object can be prevented from being damaged due to too large collision force at the grabbing moment, too slow grabbing can be prevented, and the grabbing efficiency is achieved; a thin film pressure sensor is installed to measure the magnitude of contact force, stable closed-loop control is formed, and objects are prevented from being damaged in the grabbing process; and a control circuit and a control flow scheme are further designed to guarantee stable and reliable operation of the system, and finally lossless grabbing of the soft and fragile objects is achieved.