Scientific and engineering research on soft materials requires precise structural analysis to understand their hierarchical and fluctuating nature. A new beamline, the BL03XU frontier soft-material beamline, that is dedicated to scattering experiments on soft materials was recently installed at the third-generation synchrotron facility, SPring-8, in Japan. The BL03XU uses an in-vacuum undulator, and the photon flux of the obtained X-ray can reach 1013 photons sec−1, with an energy resolution of ΔE/E≈2 × 10−4 at 12.4 keV. The BL03XU has two experimental hutches: a front one that is used for grazing-incidence scattering experiments and a second one for transmitting scattering experiments, which enables simultaneous small- and wide-angle X-ray scattering. The present paper introduces details about the instrument and some of the first scattering data measured at BL03XU, which reveals its cutting-edge design and high level of performance.