With variations of initial charging voltage and spraying distance, Mo coatings were prepared by electro-thermal explosion spraying with a constraining tube. The bonding strength, surface morphology and cross-section characteristics of the coating were analyzed. The results show that the coating is formed by liquid metal within a certain spraying distance. Based on the standard of VDI3198, the bonding strength grade of liquid spraying coating belongs to HF-1～HF-3. With the spraying distance increases, the proportion of solid particles in the explosion products increases, the bonding strength grade of the coatings decreases. The increase of initial charging voltage can decrease the maximum spraying distance of the liquid spraying coating