This study proposes the optimal passive and active damper parameters for achieving the best results in seismic response mitigation of coupled buildings connected to each other by dampers. The optimisation to minimise the H2 and H- norms in the performance indices is carried out by genetic algorithms (GAs). The final passive and active damper parameters are checked for adjacent buildings connected to each other under El Centro NS 1940 and Kobe NS 1995 excitations. Using real coded GA in H- norm, the optimal controller gain is obtained by different combinations of the measurement as the feedback for designing the control force between buildings. The propsed method is more effective than other metaheuristic methods and more feasible, although the contol force increased. The results ifn the active control system show that the response of adjacent buildings is reduced in an efficient manner.