Abstract: The influence of high pressure torsion on the microstructure and mechanical and electrical properties is elucidated for an Al–0.4Zr alloy pre-annealed at 648 K for 60 h. The transmission electron microscopy has revealed that the annealing causes the dispersive release of nanoparticles of a secondary Al ₃ Zr phase. The formation of this structure in the alloy ensures an increase in its conductivity from 50.7 to 58.8% IACS owing to a decrease in the Zr concentration in a solid solution. As established, high pressure torsion processing at room temperature of the pre-annealed alloy leads to the formation of a uniform ultrafine structure in them, as well as to the partial dissolution of Al ₃ Zr nanoparticles, resulting in higher strength and lower conductivity. It is shown that additional annealing of the ultrafine grained alloy for 1 h at 503 K results in a strength increase by 20% and the recovery of conductivity to the annealed state level (58.3% IACS).