Alzheimer’s disease is characterized by the presence of two histopathological aberrant structures, the senile plaques and the neurofibrillary tangles. The main component of these tangles is the cytoskeletal protein tau in hyperphosphorylated form. Since a main tau kinase is glycogen synthase kinase 3 (GSK-3), the use of specific GSK-3 inhibitors, like lithium, could be a potential therapy in Alzheimer’s disease. In this short article, we have done a review on tau phosphorylation in Alzheimer’s disease and other tauopathies, and on the inhibition of kinases like GSK-3, involved in tau modification.