Since China' power system has the characteristics of hierarchy structure in operation and management， traditional centralized computing patterns on the small-signal stability analysis are very difficult to meet the demands of online calculation. Based on a general distributed computation model of power systems， this paper proposes a distributed eigenvalue algorithm for the small signal stability analysis of large-scale power systems derived from analysis of essentially spontaneous oscillations in power systems（AESOPS）. The algorithm only requires exchanging data of boundary nodes during cooperative computation， which is suitable to the distributed environment of power system. This algorithm has been tested on an IEEE 39-bus system and the results verify its rationality and validity.