This paper proposes a Multi-Band Time-Frequency Spreading OFDM (MB-TFS-OFDM) system used in powerline environment in accordance with the characteristics of powerline channels and its noise, and the shortcomings of the existing technology in robustness and reliability. The system resists time variability of the powerline channels and the impulse noise through Time-Frequency Spreading technology, restrains the impulse noise and narrowband noise through the adoption of multiband technology, and resists the intersymbol interference and meets the need of speed through OFDM technology. Compared with the OFDM system, the MB-TFS-OFDM acquires a gain of 10*log (G) dB at the cost of G-times speed, and enhances the robustness of the system through the adaptive selection of the frequency band and multi-band filter. The simulation results show that the MB-TFS-OFDM performances are better than OFDM and Time-Frequency Spreading OFDM, with a performance improvement of 5dB under impulse noise environment.