In this paper, the life cycle assessment(LCA) methodology is applied to Personal Computer in materials processing stage in order to analyze the impact to the environment. LCA data collection is carried out taking into account on main materials of PC in materials processing stage. And the impact assessment is the environmental burdens on three factor in air emission(CO2, SOx, NOx), five factor in water emission(BOD, COD, SS, N, P), and three factor in transported substance(cl, NH4, SO4). According to the result, the loading in the materials processing stage of PC proved to be used total energy 6,285Mj and emitted CO2 259.8kg, SOx 3,571g, NOx 330g, COD 1,328g, P 246g, N 2,434g.