Microstructure and properties of Al-0.30Zr and Al-0.30Zr-0.08Y （mass fraction, %） alloys were investigated by electrical conductivity measurements, microhardness tests, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Micron-sized primary Al3Y phases form within grains and at grain boundaries simultaneously as product of eutectic reaction in as-cast Al-Zr--Y alloys. The addition of Y obviously accelerates the precipitation kinetics of Al3Zr （Ll2） in Al-Zr-Y alloys. The Al-Zr-Y alloys exhibit greater electrical conductivity during aging due to formation of increased volume fractions of Al3（Zr, Y） precipitates. In ternary Al-Zr-Y alloys, spheroidal L l2-structured Al3（Zr, Y） precipitates with increased number density and smaller mean radius were observed. The Al-0.30Zr-0.08Y alloys show improved recrystallization resistance compared with Al-0.30Zr alloys
