Mechanical bending effects on two important components, i.e., amorphous silicon thin film transistors and copper interconnect lines, for the flexible electronics were studied. The deterioration of the thin film transistor's performance was dependent on the bending direction, i.e., more serious along the drain current flow direction than perpendicular to the drain current flow direction. The copper line's lifetime was drastically reduced, e.g., from 30 years without bending to 7.7 years with bending. The thin film transistor damage can be reduced with the proper layout design. Therefore, the interconnect line will be a critical factor affecting the product's reliability.