The design of the Chang'E-4 lunar farside soft-landing mission is introduced in this paper. The landing area is initially selected as the Von Kármán crater inside the South Pole-Aitken basin on the lunar farside. A relay satellite is used to realize the lander and rover to the ground communication, and a Halo orbit around the second Earth-Moon Lagrangian point is chosen as its mission orbit. The relay satellite and the lander-rover combination are launched by a CZ-4C rocket and a CZ-3B rocket respectively. The lander, rover and relay satellite containing six domestic scientific payloads and three international scientific payloads, have carried out scientific exploration focusing on VLF radio astronomical observation, roving area topography survey, mineral composition and shallow structure investigation. In addition, two formation flying microsatellites on lunar orbit, lunar micro-ecosphere and large-aperture laser angle reflector are launched to carry out ultra-long-wave astronomical interferometry test, lunar surface ecosystem test and laser ranging test over the Earth-Moon distance respectively. By innovatively designing the top-level tasks, adequately inheriting mature technology and products, adding the function module of relay communication, and opening some resources to introduce high-performance payloads and test projects, a low-cost, short-duration, great-openness and high-efficiency lunar exploration mission would be achieved.