This work reports the detailed study on the magnetite–reduced graphene oxide (Fe3O4–RGO) modified glassy carbon electrode, which could be used for the selective electrochemical detection of Cd2+. The Fe3O4–RGO modified glassy carbon electrode (GCE) was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Square wave anodic stripping voltammetry (SWASV) was applied for the detection of Cd2+. The limit of detection with the Fe3O4–RGO modified electrode toward Cd2+ was calculated as 0.056μM (3σ method). The electrochemical parameters that exert influence on deposition and stripping of metal ions, such as supporting electrolytes, pH values, deposition potential and deposition time, were optimized. Besides, the interference and stability measurements were also evaluated under the optimized parameters. More importantly, selective detection toward Cd2+ was achieved. It is meaningful for electrochemical method to overcome the great challenge of improving the selectivity toward heavy metal ions.