This study explores the influence of various conventional cooling media (water, cutting fluid, and quenching oil) on the mechanical properties of FSW joints in AA7075-T61 aluminum alloy. Cooling media had minimal impact on the macrostructure of AA7075-T651 joints, though a slight increase in the amount of dynamically recrystallized grains was observed in the TMAZ. A 5-10% increase in LHZ hardness (up to 131 HV0.1) was achieved, and the HAZ width was reduced from 15 mm to 11 mm, with water-based cooling showing the best results. The use of different cooling media improved joint strength, with joint efficiency reaching up to 85.3% for a 10% Blasocut 2000 solution. The results also indicated a direct relationship between the heat absorbed by the cooling medium and the ultimate tensile strength of the joints. Although FSW enhanced strain-hardening capacity, external cooling slightly reduced this effect, with Hc values decreasing from 0.414 to 0.380.