Abstract: In this paper, ignition mechanism of tungsten-zirconium alloy fragment to fuel with steel plate shielded was investigated. The analysis of common oil-tank structure was conducted, and the oil-tank simulation target was designed. Meanwhile, the experiments on penetration and ignition of four different types of tungsten-zirconium alloy fragment to fuel with steel plate shielded was done, and the ignition process of mixture of oil and gas was obtained by high speed video. The experimental results show that tungsten-zirconium alloy fragment with the impact velocity between 800 m/s and 1 600 m/s can ignition mixture of oil and gas on the surface of diesel with 6 mm thick steel plate shielded, but it is difficult to ignition diesel; the ignition effect of tungsten-zirconium alloy fragment to mixture of oil and gas is interrelated with energy release characteristics of fragment at the back of the shielded steel plate and distribution structure of mixture of oil and gas.