Abstract This report is devoted to the characterization of the apolipoprotein E (ApoE) in Microcebus murinus.Only one allele homologous to the human ApoE4 allele was evidenced. The distribution of the corresponding ApoE protein in the brain was found in association with the pathological proteins characteristic of Alzheimer's disease (AD). Immunocytochemistry revealed brain deposits of ApoE in: (1) the cortical amyloid plaques; (2) the neurones of the various cortical lobes, the hippocampus and the brainstem; (3) the glial cells, astrocytes of the cortical parenchym and oligodendrocytes of the corpus callosum; and (4) the vessel walls. Most ApoE, β-amyloid protein, abnormally phosphorylated Tau proteins and gliofilament acid proteins were seen in the same cortical areas. These findings for ApoE report the view that Microcebus murinus,in captivity, presents a pathological profile very similar to that observed in AD.