The invention provides a piezoelectric six-dimensional accelerator sensor based on a 9-SPS parallel mechanism, and relates to an accelerator sensor. The piezoelectric six-dimensional accelerator sensor comprises a shell (1), a cubic mass block (2), nine pieces of piezoceramics (3) and eighteen flexible spherical hinges (4); wherein the mass block is positioned in the center of the shell, and the upper surface, the front surface and the side surface of the mass block which are opposite to the shell are respectively provided with three pieces of piezoceramics to form three groups of piezoceramics together; the nine pieces of piezocermamics are cylindrical, and are connected with the mass block and the inner wall of the shell through the flexible spherical hinges (4); under the initial condition, the three groups of piezoceramics have pairwise orthogonal relation; and two pieces of piezoceramics on the upper surface are parallelly arranged left and right, two pieces of piezoceramics on the front surface are arranged up and down, two pieces of piezocermamics on the side surface are arranged front and back, and each group of piezoceramics is arranged symmetrically with the center of the mass block. The piezoelectric six-dimensional accelerator sensor has the advantages of simple structure, small volume, light weight, small measurement error, high precision, high sensitivity, high isotropy, wide signal band and the like.