Recently, two new boron-rich chalcogenides, B 6 Se and B 6 S, have been synthesized at high pressures and high temperatures . The structure of materials produced under pressure is of great interest because it usually contains defects, which, in turn, affect the properties of the resulting material. The deformation that occurs during the pressure treatment introduces various defects into the material: dislocations, stacking faults, twins, etc. Localized deformation in the form of shear bands and areas of strong local flow leads to structural heterogeneity. Due to the presence of defects, the shear strength of real crystals is significantly reduced compared to an ideal crystal. The defects affect the electrical, diffusion, optical, emission, photoelectric, magnetic and other properties of the material . The aim of the present work was to investigate the real structure of new boron-rich chalcogenides, B 6 Se and B 6 S, using high-resolution transmission electron microscopy.