This paper presents the mechanism and control design of a modular XY nanopositioning stage employing flexure mechanisms and piezoelectric actuators. A new compact parallel flexure stage with two translational degrees-of-freedom is presented. The dual-stacked bridge-type amplifier is employed by a serial connection of two amplifiers. Static and dynamic analytical modeling of the XY stage are carried out, which are verified by performing finite element analysis simulations. Owing to a larger amplification ratio of the bridge-type amplifier and acceptable decoupling property, the stage exhibits a nearly decoupled two-dimensional large motion. Moreover, the adaptive discrete sliding mode control scheme is devised to achieve precise positioning for the stage. The performance and effectiveness of this presented design are verified by several experimental studies.