The Middle East syndrome coronavirus (MERS-CoV) is a recently emerging betacoronavirus with high fatality. Recently, dipeptidyle peptidase (CD26, DPP4) was identified as the host cell receptor for MERS-CoV. Interestingly, despite of common presence of DPP4 receptors the binding and infection of various cells shows imminent variability. In this report, we provide a tool for prediction of the host tropism of the virus based on the host receptor binding interface. We found out that, in the binding of MERS-CoV to cells the amino acid residues in lancets 4 and 5 of DPP4 receptor, namely K267, Q286, T288, R317, R336, Q344 A291, L294, and I295 are involved. Changes in these residues correspond to profound decrease in virus binding to cells. The nine residues at the interface between the virus spikes and the lancets 4 and 5 of host DPP4 can be used as a predictive tool for the host tropism and virus affinity to host cell receptors.