Aiming at the requirement of multidimensional test of acceleration direction under realistic environment, a “foursides and eightbeams” MEMS piezoelectric triaxial accelerometer with low g value (g=9.8 m/s2) is proposed in this paper. The structure of the accelerometer is designed according to the operating principle, and the structure parameters are analyzed and optimized by ANSYS and Matlab software. The process flow is designed and the fabrication and packaging of the sensor are realized through the key processes of ion implantation, ICP dry etching and deep silicon etching. The measured sensitivities of the sensor in the three axial directions are 44.35 SymbolmA@V/g, 49.25 SymbolmA@V/g and 232.89 SymbolmA@V/g respectively by using the precision centrifuge, and the feasibility of the design scheme is verified.