Technical developments for simple shear deformation experiments at high pressures were made. The newly designed cell assembly can be compressed by deformation-DIA apparatuses with the MA 6-6 system, which consists of six second-stage tungsten carbide anvils (with a truncated edge length of 5 mm) and the anvil guide. Deformation of samples was barely observed during the compression process, showing that the shear strain of the deformed samples can be measured by the rotation of a strain marker. Simple shear deformation experiments on anhydrous and hydrous oli-vine aggregates were conducted under upper mantle conditions (pressures of 5.2–7.6 GPa and tem-peratures of 1 473–1 573 K), and sample deformation with a shear strain of γ=0.8–1.2 was success-fully achieved at a shear strain rate of 4.0×10-5–7.5×10-5 s-1. The present study extended the pressure range of simple shear deformation experiments in the deformation-DIA apparatus from 3 GPa in an early study to 7.6 GPa at high temperatures. Technical developments for simple shear deformation experiments at high pressures were made. The newly designed cell assembly can be compressed by deformation-DIA devices with the MA 6-6 system, which consists of six second-stage tungsten carbide anvils (with a truncated edge length of 5 mm) and the anvil guide. Deformation of samples was barely observed during the compression process, showing that the shear strain of the deformed specimens can be measured by the rotation of a strain marker. Simple shear deformation experiments on anhydrous and hydrous oli- vine aggregates were conducted under upper mantle conditions (pressures of 5.2-7.6 GPa and tem-peratures of 1 473-1 573 K), and sample deformation with a shear strain of γ = 0.8-1.2 was success-fully achieved at a shear strain rate of 4.0 × 10-5-7.5 × 10-5 s-1. The present study extended the pressure range of simple shear deformation experiments in the deformation-DIA apparatus from 3 GPa in early study to 7.6 GPa at high t emperatures.