This paper presents the design, optimization, fabrication and testing of a new piezo-driven compact XY parallel stage for nanopositioning applications. A decoupled, compact parallel stage is developed by a stacked design, which provides a larger area ratio than existing piezo-driven stages. Displacement amplifiers are adopted to amplify the stroke of piezoelectric actuators. The amplifiers are then improved and integrated with the motion decoupler to isolate the two actuators. The main design variables of the stage are optimized by applying a genetic algorithm based on finite-element analysis (FEA) to achieve the required performance. The optimized design is then further improved to enhance the stage performance, which is verified by performing FEA simulation studies. A prototype stage is fabricated for experimental study. Both open-loop and closed-loop testing are conducted to validate the stage’s performance. Results show that the decoupled XY stage possesses a compact dimension of 87.2  ×  87.2 mm², which offers a workspace of 212.48  ×  219.24 µm² with a resolution of 7 nm.