A flexible microactuator with 3 degrees of freedom has been developed for Micromanipulators. It is made of fiber reinforced rubber and its deformation is controlled by an electrohydraulic or - pneumatic system. This report deals with its static characteristics. First, theoretical characteristic equations are derived based on the infinitesimal deformation theory. They are useful for practical design applications due to their simple forms. Secondly, the FEM is applied to the nonlinear analysis of large deformation. The calculated results are compared to the experimental data of the prototype (outerdiameter: 12 mm, length: 50 mm). As a result, while the theoretical characteristic equations are effective for predicting small deformation, the numerical method is for both small and large deformations.