Abstract: As-cast microstructure and Cr-Zr phases of high-strength and high-conductivity Cu-0.8Cr-0.2Zr alloy were studied by using optical microscopy,field-emission scanning electron microscopy and energy dispersive spectrometer.The results show that the microstructure of as-cast alloy was coarse columnar crystal.There were three types of chromium in the alloy,including the undissolved phase of block shape existing in the grain,massive primary phase of chain-like shape distributed in grain boundaries and the dispersively distributed secondary phase in matrix.And zirconium distributed in grain boundaries in the shape of long strip and eutectic α+Cu5Zr and also dispersively distributed in the shape of secondary phase.A few Cu-Cr-Zr of lamellar-type was also formed by ternary eutectic in the alloy.