This research was performed to investigate the effect of ageing on grain refinement of 82wt%Cu-13.5wt%Al-4.5wt%Ni-0.1wt%misch metal alloy with ageing temperature and time. The results obtained in this study are as follows; The variation of transformation temperature with ageing temperature had very influence on ageing time at 300℃. But it had not influence on ageing time at 100℃. The variation of transformation temperature after second reversed transformation cycle was not occured in martensitic phase ageing, but M, point was appeared equally with third reversed transformation cycle in parent phase ageing. The variation of M, point was not nearly with ageing time at 100℃ ageing temperature. But it was decreasing with ageing time at 300℃ ageing temperature and A, point was increasing with ageing time. Structure of parent phase ageing was being M18R martensitic and N2H martensitic phase. It was found that a and γ₂phase were created by ageing of long time at 300℃ ageing temperature.