Tauopathies are a group of neurodegenerative diseases characterized by the accumulation of the tau protein in the brain, which causes clinical dementia. The tau protein stabilizes microtubules and regulates axonal transport, however, when hyper-phosphorylated, it aggregates in the brain. Tauopaties can be divided into primary and secondary (e.g., Alzheimer’s disease). Experimental animal models are an important tool to study tauopathies. Here, we discuss molecular mechanisms of tauopathies and their available experimental models in both rodents and a relatively novel model organism, the zebrafish (Danio rerio), as well as outline novel research trends in this field.