Alzheimer's disease is most common form of dementia, most obvious risk factor for the disease is ageing. It's degenerative disease of the cells of the cerebral cortex and surrounding structures, progressive, incurable, with somatic complications and death. Typical clinical symptoms are disturbances in memory and changes in behaviour. The main pathological lesions in the brain of patients with AD are senile plaques (composed of Aβ peptide) and neurofibrillary bundles (composed of phosphorylated tau protein). Alzheimer's disease occurs in two forms, familial and sporadic, and both have a genetic basis to their formation. After decades of research, Alzheimer’s disease (AD) remains incurable and thus is considered a major human healthcare challenge. Current therapies for Alzheimer’s disease do not modify the course of disease and are not universally beneficial. Research has moved to the pre- symptomatic phases of Alzheimer’s disease, with a greater emphasis on the role of biomarkers in defining cases and monitoring response to therapy. Different aspects of research AD should contribute to the development of new forms of treatment and/or prevention of this still incurable disease.