In this paper, a flexible micro-operation platform with three degrees of freedom, large stroke, and high precision is designed to meet the higher demands in the fields of biological engineering and medicine. The platform adopts a compound lever mechanism. The theoretical magnification of the mechanism is 9.627, the simulation magnification is 10.111, and the error is 5.02%. The platform uses a piezoelectric ceramic driver to increase the output stroke to obtain a larger movement space. The composite lever mechanism and new micro-operating platform are studied by theoretical calculation and finite element simulation. The results show that the new flexible micro-operating platform based on the composite lever mechanism has good motion decoupling and high precision.