In order to realize the application of the performance-based seismic design theory in passive control structures, this paper takes the large span isolated structures as the research object and proposes a structural design framework based on random seismic response. The framework includes five parts, that is, defining the performance level of the structures, determining and quantifying the performance targets, designing isolation layer based on displacement index, calculating random seismic response of structures, and evaluating the structural reliability. An example is given to show that the proposed performance-based seismic design method combined with the reliability theory can effectively guarantee the safety of large span isolated structures under the given performance targets, which has certain guiding significance for the practice of large span seismic design.