Design status of the ECRH system for CFETR

•The conceptual design of 170 GHz, 30 MW Electron Cyclotron Resonance Heating (ECRH) system was introduced.•The design and layout of transmission lines were shown and series of microwave components were introduced.•The design of launchers based on the front steering concept was detailly described.•Layout of the quasi-optical system of an ECH&CD UL was shown.•The maximum power per port and minimize Breeding Blanket (BB) openings were evaluated by the microwave and optical design of launchers.