NOVELTY - The flexible printed circuit board (200) is formed on the motherboard (100). The reinforcing substrate (400) in which the bonding layer is formed is struck on the flexible printed circuit board. The flexible printed circuit board is separated from the motherboard. The electric component (300) is formed on the separation section of the flexible printed circuit board contacted with the motherboard.    USE - Method of manufacturing flexible electric component e.g. organic LED (OLED), liquid crystal display, electrophoretic display, plasma-display panel, thin film transistor, microprocessor, RAM, and solar cell (all claimed).    ADVANTAGE - The flexible electric component is formed efficiently using low cost. Since the electric component is formed on the separation section having the surface roughness identical with the motherboard, the surface roughness problem of the metal material flexible printed circuit board can be easily solved. The surface roughness of the flexible printed circuit board can be maintained low, the processing temperature of the planarization layer of the polymer series is lowered, the processing temperature is reduced, and the process time and cost are reduced. The expensive polishing is made unnecessary, the reservoir water rate problem due to the high defect density can be resolved, and the economical efficiency is improved. The generation of crack by the difference of the coefficient of thermal expansion of the material of the flexible printed circuit board is reduced. Since the cheap printed circuit board is used, the production cost of the printed circuit board is reduced.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) flexible electric component; and    (2) flexible printed circuit board.    DESCRIPTION OF DRAWING(S) - The drawing shows an explanatory view of the manufacturing process of the flexible electronic component. (Drawing includes non-English language text)    Motherboard (100)    Flexible printed circuit board (200)    Electric component (300)    Reinforcing substrate (400)    State in which flexible printed circuit board is formed on motherboard (A1)