An inertia measurement unit for an unmanned aircraft, comprising: a housing assembly; a sensing assembly, comprising: a first circuit board fixed on the housing assembly, a second circuit board comprising an inertia sensor that is fixedly disposed on the second circuit board, and a flexible signal line for communicationally connecting the first circuit board and the second circuit board; the inertia measurement unit further comprises: a weight block having a first surface and a second surface opposite the first surface, wherein a recess is formed on the second surface, and the second circuit board is embedded in the recess and fixed with the weight block; and a vibration damper, comprising a first vibration-attenuation cushion and a second vibration-attenuation cushion arranged on opposite sides of the weight block, wherein the sensing assembly, the weight block and the vibration damper are disposed in the housing assembly, and wherein the second circuit board, the weight block, the first vibration-attenuation cushion and the first circuit board are configured to be bonded together in sequence into one piece and then be fitted into the housing assembly, wherein the recess matches in shape with the second circuit board; wherein the first surface of the weight block is fixedly bonded to the first vibration-attenuation cushion, and wherein the second vibration-attenuation cushion is fixedly bonded to the second circuit board. a housing assembly; a sensing assembly, comprising: a first circuit board fixed on the housing assembly, a second circuit board comprising an inertia sensor that is fixedly disposed on the second circuit board, and a flexible signal line for communicationally connecting the first circuit board and the second circuit board; a first circuit board fixed on the housing assembly, a second circuit board comprising an inertia sensor that is fixedly disposed on the second circuit board, and a flexible signal line for communicationally connecting the first circuit board and the second circuit board; the inertia measurement unit further comprises: a weight block having a first surface and a second surface opposite the first surface, wherein a recess is formed on the second surface, and the second circuit board is embedded in the recess and fixed with the weight block; and a vibration damper, comprising a first vibration-attenuation cushion and a second vibration-attenuation cushion arranged on opposite sides of the weight block, a weight block having a first surface and a second surface opposite the first surface, wherein a recess is formed on the second surface, and the second circuit board is embedded in the recess and fixed with the weight block; and a vibration damper, comprising a first vibration-attenuation cushion and a second vibration-attenuation cushion arranged on opposite sides of the weight block, wherein the sensing assembly, the weight block and the vibration damper are disposed in the housing assembly, and wherein the second circuit board, the weight block, the first vibration-attenuation cushion and the first circuit board are configured to be bonded together in sequence into one piece and then be fitted into the housing assembly, wherein the recess matches in shape with the second circuit board; wherein the first surface of the weight block is fixedly bonded to the first vibration-attenuation cushion, and wherein the second vibration-attenuation cushion is fixedly bonded to the second circuit board.