In recent years, research on the hydrometallurgical process became active due to its advantages as energy saving, environmental protection and investment reduction. In this study, the effect of physical and chemical pre-treatment on metal liberation was studied as the preliminary step for the hydrometallurgy recovery of valuable metals from PCBs. The physical pre-treatment comprises crush, magnetic separation, air separation and size separation steps. The chemical pre-treatment comprises crush, chemical delamination and floatation. Two different pre-treatment processes were selected comprising the pretreatment steps. The degree of liberation of physical and chemical process was more than 90% and 100% respectively.