P>Objective In order to investigate the influence of reelin deficiency on the hippocampal development, the histochemical characteristics of hippocampal pyramidal cells and granule cells of reeler mice were analyzed, therefore, reelin’s function would be better understood with more morphological evidences. Methods With immunofluorescent double labeling, the pyramidal cells, granule cells and mossy cells in hippocampi between wild type and reeler mice were labeled. Results The development and lamination of hippocampal cortical plate were in disorder. Pyramidal cells and granule cells dispersed, and moreover, granule cells proliferated rapidly and migrated into hilus, so that the bound between granule layer and hilus disappeared. Conclusion As a stop signal and regulatory signal, reelin plays important roles in neuronal migration of developing cortical plate, especially in the regulation of granule cell proliferation/P>