[en] Graphical abstract: To capture radioactive strontium from wastewater, nanorods of WO₃ anchored to reduced grapheme oxide composite was prepared as absorbents. - Highlights: • RGO/WO₃ nanocomposite is synthesized successfully by a facile hydrothermal method. • RGO/WO₃ possesses a mesoporous 3D structure, in which WO₃ is uniformly deposited on the surface of RGO. • Combining the benefits of GO and WO₃, RGO/WO₃ exhibit excellent adsorption ability for removal of Sr²⁺. • RGO/WO₃ nanoadsorbent has high reusability and stability. - Abstract: A simple hydrothermal method was used to prepare 3D nanostructured composite adsorbents of reduced graphene oxide (RGO) and WO₃ (RGO/WO₃). The analysis results suggest that it possesses a mesoporous 3D structure, in which WO₃ nanorods are uniformly loaded on the surface of the RGO. Combining the benefits of GO and WO₃, the composites exhibit a higher adsorption capacity for removing Sr²⁺ from aqueous solutions over a wide pH range (4–11). Adsorption isotherms show that the data fit the Langmuir isotherms well (R > 0.99), and the maximum adsorption capacity of 149.56 mg g⁻¹ was achieved, much higher than that for GO, WO₃ and other similar adsorbents. Sr²⁺ adsorption on RGO/WO₃ reached equilibrium within 200 min. The fast adsorption and high adsorption rate of RGO/WO₃ are mostly attributable to the plentiful adsorption sites provided by the dispersed WO₃ nanoparticles on the RGO surface. Furthermore, the existence of Na⁺ ions has no obvious effect on the removal of Sr²⁺ ions by RGO/WO₃, and RGO/WO₃ adsorbent can be repeated at least 5 times without significant loss of adsorption capacity by adsorption-desorption experiment. Thus, RGO/WO₃ shows the potential ability for removal of ⁹⁰Sr from radioactive wastewater.