Pulsed high energy density plasma (PHEDP) is a new material modification technique, which has the features of: high energy density (1-10 J/cm(2)), high plasma density (10(14)-10(16) cm(-3)), high electron temperature (10-100 eV), high directed plasma velocity (10-100 km/s) and short pulse duration (10-100 mus). PHEDP interacting with material will result in rapid melting and re-solidification of surface layer with a quenching rate up to 10(8) K/s; thus the material surface properties are modified. At the same time, PHEDP contains condensable ions or/and atoms, so a thin film layer can be formed on the modified surface and the deposited layer can be mixed with the substrate (or previous deposited layer) during following pulses. Therefore, this technique actually combines film deposition and mixing into one step. In this paper, we have reported the research results on the metallization of Si by PHEDP. The Ti-Si reactions under PHEDP are also discussed.