Based on the introduction of the critical angle, a new method for multidimensional performance limit states is developed to analyze the structural fragility of plane irregular frame-shear-wall structures. First, the critical angle of seismic wave is determined using the wavelet transform in Matlab. Then, concerning the dependency of the limit states, the probability of exceedance can be calculated by adopting the inter-story drift and inter-story torsion angle as the quantitative indexes. The fragility curves are achieved under two dimensional performance limit states. Using this method to analyze the aforementioned structure, the fragility curves under four performance levels are obtained, which are normal operation, immediate occupancy, life safety, and collapse prevention. The results indicated that the critical angle of seismic wave has a significant impact on the performance of the plane irregular structures. In order to avoid overestimating seismic performance of plane irregular structures, inter-story drift and inter-story torsion angle should be simultaneously considered. Therefore, for plane irregular estimate, the analysis method of fragility under multidimensional performance limit states is more safe and reliable.