Double immunofluorescent stainings of neurofibrillary tangles (NFT) were performed using anti‐tau, ubiquitin, amyloid P component and neurofilament antibodies. A confocal laser scan microscope was used to investigate the distribution and the relationship of these components. Tau‐ and ubiquitin‐immunoreactivities (IR) were observed in the same NFT. Tau‐ and neurofilament‐IR were observed in the same neuron. Tau‐ and amyloid P com‐ponent‐IR were not colocalized in the same NFT. These findings may suggest a process of NFT‐formation which will help in the understanding of pathophysiology of Al