Based on the empirical electron theory (EET) of solids and molecules, the valence electron structures (VESs) of TiC-Mo(Ni)-Fe system were calculated by building proper structure model. The results indicate that additives of Mo and Ni improve the interface conjunction factors of the cermets in different ways. By adding Mo, the VESs of the ceramic phase are improved for the formation of the rim phase (Ti1-xMox)C, which leads to the enhancement of the interface conjunction, while the improvement of the VESs on metal phase by adding Ni is due to the formation of the Fe100-yNiy. Mo and Ni additives increase the interface electron density of cermets, that is, the adding of the Mo and Ni enhance the overlapping grade of the electron cloud on interface and increase the binding energy of the interface, which is propitious to the wettability. The best wettability was found at x=0.5 or y=30.