ABSTRACT A three-wall piston-cylinder type high pressure cell for muon-spin rotation/relaxation experiments was designed, manufactured, tested and commissioned. The outer cylinder of the cell body is made from MP35N and the middle and inner cylinders are made from NiCrAl nonmagnetic alloys. The mechanical design and performance of the pressure cell are evaluated and optimised using finite-element analysis. The outcomes of the experimental testing closely match the modelling results. The high pressure cell is shown to reach pressure of up to 3.3 GPa at ambient temperature, corresponding to 3.0 GPa at low temperatures, without irreversible damage.