The performance of an Aquatic Clean Energy Harvester (ACEH) under the wake interferences of different arranged stationary cylinders is numerically studied. Nine wake interferences are generated by varying the transverse distance between the two stationary interfering cylinders (SIC) and the streamwise distance between SIC and the Energy harvesting Cylinder (EHC). The mass ratio, damping and spring stiffness of the ACEH are set as 1.6674, 2.7274 N s/m and 758.11 N/m, respectively. The wake interference can induce the EHC to galloping at some particular positions. The maximum values of the output power and the conversion efficiency of the ACEH were 0.82 W and, respectively. Besides, even when the SIC does not induce galloping on EHC, the output power and the conversion efficiency of the ACEH are higher than those of the single-cylinder. The performance of the wake interference is beneficial to energy harve 10.13% sting. As the distance between the SIC and the EHC increases, the wake interference of the SIC gets weaker and the energy harvesting performance of the ACEH reduces gradually. Finally, the influence is comprehensively divided into three different regions: promotion region, disturbed region, and weak region.