Design and fabrication of structurally optimized absorbents are important for wastewater treatment such as dyes and heavy metals removal. Herein, we reported the core@double-shell structured magnetic halloysite nanotube nano-hybrid absorbent with target micro-structure and high efficiency removal capacity of dyestuffs. Our core@double-shell structured absorbent consisted of a halloysite nanotube as skeleton, an intermediate magnetic nanoparticles coating with more specific surface area and magnetic separation property, and poly(DA + KH550) derivate layer outside provided active adsorption sites. This well-defined core@double-shell configuration was quite distinct from conventional core-shell or hybrid structures. The integrated advantages of HNTs skeleton, Fe3O4 nanoparticles inner shell and poly(DA + KH550) outside shell contributed to the high adsorption capacity of methylene blue (up to 714.29 mg g(-1)) and excellent cycling stability. Furthermore, the novel core@double-shell structured absorbent exhibited better removal efficiency for methylene blue in solution with high pH, and the adsorption process can be described by using the pseudo-second-order model. More importantly, the recycling process of adsorbents was more energetically and economically sustainable by using a permanent magnet. The characteristic high removal capacity, cycling stability and easy separation made core@double-shell structured absorbent promising for the efficient removal of dyestuffs from the wastewater.