The effect of Be on the mechanical properties of a Cu-Zn-Al alloy has been studied Beryllium addition of 0.27 wt% or 0.66 wt% reduced the grain size of the alloy by a factor of 4, to 250-300㎛. The fracture stress and the fracture strain of the alloy with Be addition were 2-4.5 times as great as those of the alloy without Be. The alloy with Be addition showed an improved shape memory effect an increased fatigue life by thermal cycling, a good formability and a ductile transgranular fracture mode.