The invention belongs to the technical field of rare metal extraction, in particular to a method for preparing TiCl3 by electrorefining a Ti electrolyte. The technical problem to be solved by the invention is to provide a method for preparing TiCl3 by electrorefining the Ti electrolyte, which comprises the following step: the electrolyte and anhydrous NiCl2 are mixed and reacted. The method of theinvention can effectively oxidize the divalent titanium in the electrolyte to trivalent titanium, and the total titanium recovery rate is above 95%.