The utility model discloses a free-form surface optical reflector for a light emitting diode (LED) motorcycle dipped headlight. The inner surface of the reflector is a free-form surface which forms an optical reflecting surface; an opening for installing an LED is arranged on the bottom surface of the reflector, a light exit port of the reflector is arranged at one end which is right opposite to the bottom surface, most of light emitted by an LED light source is reflected by the inner surface of the reflector and then exits to a lighting surface, and the rest light directly exits to the lighting surface; the reflector is divided into an upper portion and a lower portion, and the free-form surface of the upper portion of the inner surface of the reflector mainly reflects light which is emitted above the horizontal plane to the lighting surface below the horizontal plane; and the free-form surface of the lower portion of the inner surface of the reflector mainly converges light which diffuses below the horizontal plane to the lighting surface below the horizontal plane. The free-form surface optical reflector is simple in structure, convenient to install, high in light-use efficiency and capable of effectively controlling directions of the light and inhibiting glare effects and meets light distributing requirements of GB5948-1998.