Although a few automated hippocampal subfields segmentation methods have been developed, there has been no in vivo Magnetic Resonance Imaging (MRI) study on the hippocampal subfields volumes of Late Life Depression (LLD). The aim of this study was to investigate the hippocampal subfields volume differences between LLD subjects and healthy elderly controls using an automated hippocampal subfields segmentation technique. Thirty subjects with LLD and 30 group-matched healthy control subjects underwent 3T MRI scanning, and hippocampal subfields volumes were measured and compared between the groups. Subjects with LLD exhibited significant hippocampal volume reductions in the total hippocampus, subiculum, and Cornu Ammonis (CA) 2-3 areas compared with healthy subjects (uncorrected, p<0.001). This study is the first to elaborate the subfields volume differences of both hippocampi between controls and LLD patients. These structural changes in the hippocampal presubiculum, subiculum, and CA2-3 areas might be at the core of the underlying neurobiological mechanisms of hippocampal dysfunction in LLD.