Song and Mason equation of state (EOS) with a simple modification has been extended to modelling PVT properties of ionic liquids (ILs). The considered ILs are [C1mim][MeSO4], [C1mim][CH3OC2H5SO4], [C1mim] [(CH3)2PO4], [C2mim][MeSO4], [C2mim][BF4], [C2mim][SCN], [C2eim][NTf2],[C4mim][C(CN)3], [C4mim][CF3SO3], [C4mim][SCN], [C5mim][NTf2], [C8mim]
[NTf2], [(C6H13)3P(C14H29)][Cl], [(C6H13)3P(C14H29)][NTf2], [(C6H13)3P (C14H29)][Ac], [C3mpyr][NTf2], [C4mpyr][NTf2] and [Py][C2H5OC2H4SO4].Three temperature-dependent parameters in the proposed EOS have been scaled as functions of reduced temperature with the use of the law of corresponding states. It is shown that the knowledge of just critical temperature and critical density is sufficient to predict the PVT properties of these ILs. The overall average absolute deviation of calculated densities from literature values for 1347 data points of 18 ILs was found to be 0.58%. The predicted density of ILs from proposed EOS has been compared with those obtained by other literature work. Moreover, we indicate that the Zeno line regularity can well be predicted by proposed model for ILs.