Ning et al.(2015) developed a 2D fully nonlinear potential model to investigate the interaction between focused waves and uniform currents.The effects of uniform current on focusing wave crest,focal time and focal position were given.As its extension,harmonic energy transfer for focused waves in uniform current is studied using the proposed model by Ning et al.(2015) and Fast Fourier Transformation(FFT) technique in this study.It shows that the strong opposing currents,inducing partial wave blocking and reducing the extreme wave crest,make the nonlinear energy transfer non-reversible in the focusing and defocusing processes.The numerical results also provide an explanation to address the shifts of focal points in consideration of the combination effects of wave nonlinearity and current. Ning et al. (2015) developed a 2D fully nonlinear potential model to investigate the interaction between focused waves and uniform currents. These effects of uniform current on focusing wave crest, focal time and focal position were given. As its extension, harmonic energy transfer for focused waves in uniform current is studied using the proposed model by Ning et al. (2015) and Fast Fourier Transformation (FFT) technique in this study. It shows that the strong opposing currents, inducing partial wave blocking and reducing the extreme wave crest , make the nonlinear energy transfer non-reversible in the focusing and defocusing processes. numerical results also provide an explanation to address the shifts of focal points in consideration of the combination effects of wave nonlinearity and current.