The invention discloses a reconfiguration method for power distribution networks. The method includes the following steps: (1) establishing a main program module, and initializing a population; (2) updating a colony, establishing an IEDA module, and setting a population updating rule; (3) judging whether the updated colony is a radial network, establishing a power distribution network load flow calculation module if yes, calculating power losses and node voltage, and returning to step (2) colony updating if no; (4) establishing a prior distribution probability model and a conditional probability model, and establishing a posterior probability model; and (5) performing sampling from the posterior probability model to generate a new colony.