Association of ABCA1 polymorphisms and AD has been studied in different population and there are some positive and some negative results.[7][8][13][15][17][20][21] Raygani et al. showed that APOE- ε4 allele was a risk factor in developing AD in Iranian population but the protective role for APOE- ε2 against AD in this population was not statistically significant.[22] This study determines the association between sporadic AD and the human ABCA1 and APOE gene polymorphisms in an Iranian population. This evidence concerns the gene APOE and Alzheimer disease.