The invention relates to the field of laser processing manufacture, in particular to a laser shock precision forming method and a device. The device comprises a laser, an outer light path system, a laser shock head system A, a flying optical processing system with a laser shock head system B, a test sample system, a detection feedback system, a multi-axis link machine tool and a tool fixture system, a central control processor and a control system. A laser beam emitted by the laser is split by the outer light path system and are respectively transmitted to the front and the rear surfaces of a workpiece to subject the front and the rear surfaces of the double-sided workpiece with an energy absorption layer and a confinement layer to laser-induced shock wave. According to the requirements of the shape and the formation rule of a plate material, the double-sided laser shock head can execute simultaneous and non-simultaneous shock, counter shock, staggered shock, shocks with same and different energy, etc., so that the plate material is formed by generating a certain plastic deformation and a stress field distribution and that a certain residual stress is formed on the surface of the plate material. The method can achieve accurate quantitative formation, good repeatability and high forming efficiency, and can easily achieve automatic production.