In view of the amyloid hypothesis of Alzheimer’s disease (AD), the key molecular event is the structural transition of β-amyloid from the physiologically normal monomer state to soluble neurotoxic oligomers accumulating in the form of insoluble extracellular aggregates (amyloid plaques) in brain tissues. Zinc ions are known to play a crucial role in the formation of these pathological aggregates. The authors and collaborators have identified that the certain chemical modification and point amino acid substitutions in the metal-binding domain play a critical role in the formation of neurotoxic zinc-dependent oligomers and induce the development of cerebral amyloidosis and other pathological processes characteristic of AD. The results allow to use these forms of β-amyloid as potential biomarkers of early diagnosis of AD. Zinc-dependent dimerization and oligomerization of β-amyloid can be used as drug target for treatment of AD.