The microminiature inertial measurement system, a new style of the inertial measurement system, has many advantages compared with the traditional one, such as small size, light weight, low cost, little power consumption, high bearing capacity and long life. Undoubtedly, it will have wider applications in military and commercial fields. However, it is a pity that current micro inertial sensors do not have enough accuracy. Therefore, its applications were limited to some extent. This paper described a design of microminiature inertial measurement system and its composing and operating theory. In addition, its performance and applications were evaluated.