Objective The role of the cerebellum in tremor genesis is poorly understood. We measured the quantitative parameters of tremor caused by cerebellar/brainstem lesions to determine the relationship between the localisation of the lesion and the tremor characteristics. Methods We recorded the hand tremor of 77 patients using biaxial accelerometry in resting, postural and intentional position. Center frequency, frequency dispersion, proportional power of 0.9–3 Hz range and intensity were determined. Lesions on MRI/CT scans in inferior olive, cerebellar peduncles, dentate nuclei, cerebellar cortex, red nuclei, substantia nigra were investigated. Results Only 30% of patients with cerebellar/brainstem lesions had pathologic tremor. Tremor was present in postural and intentional position and was characterized by narrow frequency dispersion, a center frequency of 2.4 Hz, and normal intensity. Medulla oblongata lesions caused low intensity tremor, whereas mesencephalon lesions enhanced tremor intensity. In most cases tremor recovered within 4–6 weeks. Discussion Cerebellar/brainstem lesions cause pathologic tremor in 1/3 of the cases. Due to its low intensity and low frequency quantitative measurement is necessary to detect this kind of tremor. Tremor induced by acute lesions in the cerebellum/brainstem tends to recover. Conclusions Tremor evoked by structural lesion of the cerebellum/brainstem is related to a widespread network dysfunction rather than a deficit of a well characterised tremor generator. Significance Our study is the first which provides systematic study on the quantitative parameters of tremor caused by cerebellar/brainstem lesion, and on the relationship between tremor characteristics and the localisation of the lesion.