This article presents a novel concept design and optimal design of an ultra-precision XYθz flexure and PZT stage with nanometer accuracy. The stage consists of a regular triangle monolithic flexure mechanism with three piezoelectric actuators, and the stage uses a parallel mechanism. Since the relationship between the variables of the hinge parameters and system performances are complicated, it is very difficult to set design variables manually. Therefore, optimal design is used. Using the optimal design results, a FEM simulation was performed. The stage was designed to simultaneously attain ±50 μm in the X and Y directions and ±0.025° in the yaw direction, and have a first resonant frequency of 207 Hz in the yaw direction. The main purpose of this novel stage is to design appropriate measurement equipment; for biological specimens in particular, the stage was designed as a hollow type and with a compact size (330 mm × 330 mm × 50 mm).