The accuracy of inertial instruments such as gyroscopes and accelerometers is extremely sensitive to the dimensional changes in the components.With the in-depth research on the accuracy and stability of inertial instruments,it is found that the dimensional instability of materi-als is one of the main reasons for the poor stability of accuracy.Starting from the commonly used materials for inertial instrument components,a systematic review of the influence of microscopic defects,the second phase,grain and texture,internal stress and environmental factors on the di-mensional stability is presented from the perspective of materials science,and the way to improve the long-term stability of inertial instrumentation accuracy is proposed from the material endow-ment characteristics,and the future direction of inertial instrumentation materials and process de-velopment is prospected.