This study presents impact properties and interfacial strength of Ultra-high molecular weight polyethylene fiber plain woven fabric reinforced vinyl ester composites with different matrix volume fraction. The interfacial strength was found to be decreased by reducing the matrix volume fraction. Stress, strain and energy absorption per thickness in the impact process were evaluated and the relation between these impact parameters and interfacial strength of the laminates were investigated. The maximum stress was decreased and the maximum strain was increased with the drop of interfacial bonding strength. The experiment results also revealed that the sample with a matrix volume fraction 23% showed higher energy absorption than other ones.