In China, two-stage seismic design is generally adopted for the underground structures. The target of seismic fortification is generally "not damage in moderate earthquake, repairable in major earthquake", which is higher than ground structures. The performance index of "repairable in major earthquake" in the specification is expressed as the interlayer displacement angle, but the basis for determining the limiting value of interlayer displacement angle is not clear. Taking this seismic performance index of the underground structure in the "repairable" state as the research object, firstly, the limiting values of interlayer displacement angle in the "repairable" state in the common seismic design specifications at home and abroad are compared, and the reasons for the difference between the performance indexes of the different specifications are analyzed. Then, according to the statistic results of pseudo static tests of frame structures and shear wall structures at home and abroad, the rationality of the limiting value of interlayer displacement angle in "repairable" state in the seismic specification of China is evaluated. Finally, taking a metro station and a ground frame structure as the examples, the laws of damage and failure of the underground and ground structures are compared and studied by pushover analysis. The difference of the limiting values of interlayer displacement angle in the "repairable" state between the underground structure and the ground structure is compared. The research results can be referred for the revision of underground seismic design specification.