The invention discloses a redundancy configuration structure of an inertial measurement unit. According to the redundancy configuration structure of the inertial measurement unit, an IMU1 is installed on the lateral side 1 of a regular tetrahedron, the center of the bottom surface of the IMU1 coincides with the center of the lateral side 1, the X1 axis of the IMU1 is parallel to the side BD, the Y1 axis of the IMU1 is perpendicular to the side BD, the X1 axis, Y1 axis and Z1 axis of the IMU1 coincide with the X axis, Y axis and Z axis of a carrier coordinate system respectively, an IMU2 and an IMU3 are embedded in the lateral side 2 and in the lateral side 3 respectively, the center of the bottom surface of the IMU2 coincides with the center of the lateral side 2, the center of the bottom surface of the IMU3 coincides with the center of the lateral side 3, the Z1 axis of the IMU1 is arranged facing the outside and is perpendicular to the lateral side 1, the Z2 axis of the IMU2 and the Z3 axis of the IMU3 are arranged facing the outside and are perpendicular to the lateral 2 and the lateral side 3 respectively, the Y1 axis of the IMU1, the Y2 axis of the IMU2 and the Y3 axis of the IMU3 are all perpendicular to the bottom edges and point to the peaks of the regular tetrahedron, then the X1 axis, the X2 axis and the X3 axis are parallel to the bottom edges, and the redundancy configuration structure with the three IMU modules arranged in an oblique crossing mode is formed. According to the redundancy configuration structure of the inertial measurement unit, MAUV omni-posture navigation is achieved, and reliability of a navigation system is improved remarkably.