By the means of introducing Ward and REI equivalent partition, the solution thoughts of multi-area power system reactive power optimization parallel algorithms based on Ward and REI equivalent are analyzed and explained in this paper, and the calculation methods of external equivalent network correction and outer coordination which used in two kinds of equivalent parallel algorithm are summarized, the multi-area reactive power optimization parallel calculation are implemented by using Matlab parallel computing platform and COW/Cluster hardware platform based on master-slave parallel calculation mode. Finally testing results on IEEE 39-bus, a 538-bus practical system and a 695-bus practical systems are used to analyze and compare the computing properties of two kinds of equivalent algorithm comprehensively in comparison with the centralized optimization method.