In current study, serum IL-4, IL-6, IL-10, TNF-α, TNF-β, and CCL-2 were enrolled as observation indexes to compare the levels of serum inflammatory cytokines between patients with AD and normal controls and to evaluate the correlation between peripheral blood inflammatory cytokines and cognitive function, in order to offer basis to the diagnosis of AD. The gene discussed is IL6; the disease is Alzheimer disease.