Background The oil complex is the leading branch of the Russian industry, which includes the extraction, processing, transportation and marketing of petroleum products. This industry is considered a key indicator of the development of not only the Russian, but also the global energy market. To date, 336 companies in 34 regions of the country are engaged in oil production in Russia. Since the places of oil production are remote from the centers of its processing and consumption, the transportation of raw materials and finished products becomes important. One of the most important technological parameters of oil and petroleum products, which is often analyzed by petrochemical laboratories, is viscosity. The choice of pumping technology, energy consumption for oil transportation depends on it. The viscosity can be found in the quality certificate of diesel fuel, lighting and aviation kerosene, lubricating oils and other petroleum products. The viscosity of the substances is determined with special equipment such as viscometers. Laboratories are faced with the task of choosing a suitable device among the various types of viscometers. Aims and Objectives The purpose of this work is to conduct a comparative analysis of rotary viscometers of various modifications in terms of technical and metrological characteristics. Results The analysis was carried out on the basis of the data obtained from the descriptions of the type of measuring device No. 41702-16 «Viscometers OFITE, modification 1100», No. 35936-07 «Viscometers OFITE, modifications 800, 900» and No. 72700-18 «Rotational viscometers HAAKE». The object of the research is OFITE viscometers of modifications 1100, 900, 800; viscometers HAAKE modifications Viscotester 1 plus, Viscotester 2 plus, Viscotester C versions L and R, Viscotester D versions L and R, Viscotester E versions L and R. Viscometers HAAKE modifications Viscotester 1 plus and Viscotester 2 plus have a high level of software protection against unintentional and intentional changes, viscometers rotational HAAKE modifications Viscotester C versions L and R, Viscotester D versions L and R, Viscotester C, D, E L and R versions are low. The widest operating temperature range belongs to the HAAKE viscometer of the Viscotester E modifications, the L and R versions, the narrowest - to the OFITE viscometer of the 1100 modification. Among the considered devices, OFITE viscometers of modifications 800 and 900 provide the widest range of measurements. However, it is impossible to single out a specific device among all those considered, since the choice of one or another viscometer depends on the goals, the measurement conditions and the sample under study.