Designing highly active material to fabricate high-performance glucose sensor was great importance for diabetes treatment. In this work, we develop a novel nanocomposite composed of multilevel nanostructure with ultrathin CuxO nanoflakes anchored on Cu2O nanowires, directly on Cu foil and its application as non-enzymatic glucose sensor. Due to more active sites endowed by the ultrathin CuxO nanoflakes, the as-prepared CuxO nanoflakes/Cu2O nanowires@Cu nanoarray exhibit high sensitivity (3.59 mA mM(-1) cm(-2)), low detection limit (0.69 mu M), high selectivity, fast amperometric response (~ 2 s) and excellent reliability in human serum. And the sensitivity of ultrathin CuxO nanoflakes/Cu2O nanowires@Cu nanoarray was 1.9-fold than that of Cu2O nanowires@Cu nanoarray. Such novel multilevel nanoarray synthesized by convenient method provides a facile way to design metal oxide nanomaterial for promising non-enzymatic glucose sensor.