Abstract The simple model for the calculation of phonons in multicomponent alloys is presented in this paper. This model represents an extension of the models for three-component mixed crystals based on the modified random element isodisplacement (MREI) model. The starting parameters of this model are the lattice constants, the dielectric constants and the phonon modes of boundary binary compounds as well as the corresponding impurity modes. We applied this model on the quaternary alloys Hg 1 − x Mn x Te 1 − y Se y , Zn 1 − x Mg x Se 1 − y Te y , Al 1 − x − y Ga x In y P and Cd 1 − x − y Zn x Mn y Te. Obtained results for the whole range of composition are shown in the 3D form. Our results are in good agreement with the available experimental data from literature.