The invention discloses a graphene field effect opto-transistor comprising, from the bottom to the top in turn, a Si/SiO2 composite wafer of a Si layer and a SiO2 layer, n layers of graphene layers, n=1-2, and two gold electrodes which are separated from each other and arranged on one plane, wherein a CdSe quantum dot layer is arranged between the two gold electrodes, and diameter of a CdSe quantum dot in the CdSe quantum dot layer is 3-8nm. A manufacturing method of the graphene field effect opto-transistor is that: the graphene layers stripped from graphene crystal by using adhesive tapes are pasted on the cleaned Si/SiO2 composite wafer; polymethyl methacrylate is spin-coated on the graphene layers, and the gold electrodes are generated by etching coating layers via using an electron beam exposure method; Ni and Au are deposited on the electrodes in turn to act as a source electrode and a drain electrode via using an electron beam evaporation method, and a CdSe quantum dot solution is prepared; and the CdSe quantum dot solution is coated on the graphene layers between the two gold electrodes. The invention provides a new type of field effect opto-transistor.