Graphene oxide/polyamidoamines dendrimers (GO/PAMAMs) composites were synthesized viamodifying GOwith 2.0 G PAMAM. The adsorption behavior of the GO/PAMAMs for acid Bordeaux B (ABB)was studied and the effects of media pH, adsorption time and initial ABB concentration on adsorptioncapacity of the adsorbent were investigated. The optimum pH value of the adsorption of ABB ontoGO/PAMAMswas 2.5. Themaximumadsorption capacity increased from325.78 to 520.83mg/gwith theincrease in temperature from298 to 328 K. The equilibriumdata followed the Langmuir isothermmodelbetter than the Freundlich model. The kinetic study illustrated that the adsorption of ABB ontoGO/PAMAMs fit the pseudo-second-order model. The thermodynamic parameters indicated that theadsorption process was physisorption, and also an endothermic and spontaneous process.