Aiming at the problem that the internal space constraints and motion parameters of guided munitions are difficult to accurately measure in the high overload environment, a frame-type embedded micro inertial measurement unit (MIMU) structure is designed. The MIMU is composed of a three-axis MEMS gyroscope and a three-axis MEMS accelerometer. The weight and volume of the MIMU are greatly reduced by reasonably configuring the installation method of the sensor and optimizing the internal space layout. The overall structure of the MIMU adopts the high strength metal material and special potting process, which ensures its high overload resistance performance. Through finite element simulation and analysis, the results show that the structure of MIMU can meet the overload impact of not less than 20 000g(g=9.8 m/s²). Finally, the penetration overload test has been carried out by carrying the MIMU on the certain type of test projectile in the shooting range. The test results also show that the designed MIMU has the ability to resist high overload and meet the high overload requirements of guided munitions.