Abstract: The high-pressure beamline at High Energy Photon Source (HEPS) is designed for structural studies of matter under extreme conditions by integrating micro- and nanoscale X-ray diffraction/scattering techniques with diamond anvil cell technology. Benefiting from the low emittance, high brightness, and high coherence of the fourth-generation synchrotron source, the beamline employs an in-vacuum undulator and liquid-nitrogen cooled Si(111)/Si(220) double-crystal monochromator to deliver X-rays over an energy range of 20–70 keV. Combined with compound refractive lenses and advanced Kirkpatrick–Baez mirrors, the beamline provides focused X-ray beamsize better than 5 μm and 200 nm at different sample positions, with photon flux exceeding 3 × 10¹² photons/s. Based on experimental requirements and focusing techniques, the experimental station is divided into three platforms: a general-purpose platform, a laser-heating platform, and a sub-micrometer platform, coupled with low-temperature, high-temperature, and rapid-loading devices, which can provide a range of in situ structural characterization methods, including powder X-ray diffraction, single-crystal X-ray diffraction, radial X-ray diffraction, and atomic pair distribution function analysis, etc. This paper will present an overview of the beamline’s main performance parameters and methodological commissioning progress, demonstrate the capabilities of various experimental methods through application examples, and provide an outlook for future developments. The aim is to help researchers in relevant fields understand the features and potential of this beamline and to promote its broad application across multiple disciplines.