Equilibrium swelling data with a range of solvents for non-filled cured rubber samples were used to determine Hansen three-dimensional solubility parameters (HSPs) of seven HNBR grades with nominal acrylonitrile contents from 21 to 49 % using the HSPiP computer program. The results showed that the increase of acrylonitrile contents for HNBR grades led to increase of polar component (delta (p)) and hydrogen bonding component (delta (h)), but with little changes of dispersion component (delta (d)). By using the so far obtained HSPs it is possible to explain and predict the swelling behaviors of the fully formulated HNBR-based vulcanizates in industrial oils (IRM 903 was selected for testing), in a reference bio-fuel (Fuel C was selected for testing) and in bio-diesel (FAME was selected for testing). In these liquids, the volume swellings decreased with increasing of Ra values (calculated by HSPs), and to a certain extent, can be calculated with a modified Flory-Rehner equation by assuming that fillers would not swell in question.