Conventionally, biomedical signals are measured in the state of stillness. However, when we want to get biomedical signals on all time, we need to get biomedical signals on a state of moving body. On the state, noise signals and biomedical signals are mixed. Then, in this paper, we consider a method for removing noise signals from mixed signals using blind source separation method. In a conventional blind source separation, we assume linear channel for mixed process. But, in many cases, the channels for biomedical signals are non-linear channel. So we cannot use the conventional method. Then, we present method channel using Volterra series, and we propose a new blind source separation method for non-linear channel. Finally, we confirm a validity of the proposed algorithm by computer simulation.