In this study, we proposed a simple method for preparing triamine-bearing activated rice husk ash material (TRI-ARHA) as an advanced functional material with high nitrate adsorption capacity and durability. The novel TRI-ARHA was generated via a post-synthesis grafting method and modified by acidification to form ammonium moiety. TRI-ARHA was then characterized by using thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy and SEM-mapping. The TRI-ARHA had high nitrate adsorption capacity of 163.4 mgNO3 -/g, which was 2.06 times higher than that of a commercial anion exchange resin (Akualite A420) due to strong interactions of Si, C, and N in the material structure. This functional material with good durability after 10 cycles could be very promising for adsorption of other anions (e.g. sulfate and phosphate) in water and wastewater treatment.