The present invention provides a COF flexible printed wiring board whose insulating layer is not melt-adhered to a heating tool, and which exhibits no drop in bonding strength during panel bonding carried out after mounting of semiconductor chips, whereby reliability and productivity of a semiconductor chip mounting line is enhanced. The invention also provides a method of producing the COF flexible printed wiring board. The COF flexible printed wiring board including an insulating layer; a wiring pattern, on which a semiconductor chip is to be mounted, the pattern being formed of a conductor layer provided on at least one surface of the insulating layer; and a releasing layer, wherein the releasing layer is provided on the surface of the insulating layer opposite the semiconductor-chip-mounting surface, and is formed from a release agent containing a silicon-containing compound in such a thickness that Si intensity, as determined by means of a wavelength dispersive X-ray fluorescence analyzer, falls within a range of 0.15 to 2.5 kcps.