In this study, the perturbed hard sphere chain equation of state (PHSC EoS) has been used for the prediction of the wax disappearance temperature (WDT) in n-alkane mixtures. The PHSC EoS can thermodynamically predict the properties of high-molecular-weight compounds and chain-like molecules. The WDT of binary and ternary n-alkane mixtures have been predicted thermodynamically without using any fitting parameter. The liquid and solid phases are described by PHSC EoS based on multi-solid phase theory. The results have shown that the PHSC EoS is capable to predict the WDT of a n-alkane mixture by reasonable accuracy in comparison with experimental data.