In this work, floc-flotation has been introduced into the elimination of graphene oxide (GO) from water for the first time, so as to reduce its potential risk and biotoxicity. Fourier transform infrared spectroscopy (FTIR) and atomic force microscope (AFM) were used to characterize the prepared GO, and the floc-flotation of GO have been studied both experimentally and theoretically. Extended DLVO theory has been applied to predict the hydrophobic agglomeration of GO, while the effects of dodecylamine hydrochloride (DAH) concentration, pH and stirring strength on the floc-flotation have been discussed. It has been found that the addition of DAH could induce GO surfaces hydrophobic, while appropriate stirring strength provided the kinetic energy for overcoming the energy barrier between the approaching particles. As a result, the hydrophobic agglomeration of GO could be greatly promoted and then the flotation separation of flocs from water could be efficiently realized. This processing could remove up to 98% of the GO nanoparticles form water, resulting in a much less environmental concern for GO in natural water bodies.