Tremor is, by definition, a rhythmic oscillatory movement of a body part. It is the most common movement disorder encountered in clinical practice and can exist as a stand-alone clinical disorder or may be part of a broader spectrum of symptoms of a disease. Given the numerous causes that can lead to the appearance of tremor as well as the similarities in clinical features among different types, differential diagnosis of tremor is important in order to establish the exact cause and appropriate therapy in the treatment process. The often used classification of tremor is based on clinical presentation and distinguishes two main groups based on activity: tremor at rest and tremor during activity. Tremor during activity includes postural, kinetic, task-specific, and isometric tremor. Resting tremor directs the diagnosis towards Parkinson's disease, but also depends on the assessment of the presence of other signs of parkinsonism. The most common causes of postural tremor are essential tremor, physiological tremor, and drug-induced tremor. Differential diagnosis should also consider less common causes such as dystonic, psychogenic, cerebellar or metabolic tremor caused by hyperthyroidism which is also important to identify. A comprehensive patient assessment is needed to establish the correct diagnosis. Therefore, the aim of this thesis is to provide an overview of differential diagnosis of tremor, with an emphasis on clinical characteristics and diagnostic methods, which will help to understand the different causes of tremor and is a crucial step in further selecting appropriate therapy.