Objective To explore the expression of Bcl-2 during mouse kidney development. Methods Fifty-five Kunming mice from embryonic day 16(E16d), 18 and postnatal day 1(P1d), 3, 5, 7, 14, 21 were chosen to be used to investigate the expression of Bcl-2 on epoxy sections with immunohistochemistry technique and stereological methods. Results During mouse kidney development, the positive staining of Bcl-2 was mainly observed in proximal tubules. The increase with numerical area density(N A) of Bcl-2 was the fastest from E18d to P1d, while not much changed after P7 d. Conclusion During the pristine kidney development, the expression of Bcl-2 influences survival or death of proximal tubule.