Diethylenetriamine (DETA) modified inverse opal (IO) poly (glycidyl methacrylate-co-divinylbenzene) PGMD-DETA) was fabricated through the water-soluble colloidal crystal template and further applied as salicylic acid (SA) adsorbent with the ultrahigh adsorption capacity in aqueous solution. Compared that with the reported adsorbents, IO PGMD-DETA possessed the performance of ultrahigh adsorption capacity, comparatively short equilibration time, and relatively good reusability. The influences of the specific surface area and group content on adsorption capacity showed that the high content of group was favorable to improve the hydrophilicity and polarity of the materials, resulting in high adsorption capacity. IO PGMD-DETA-95 (the number of 95 is the mass ratio of GMA monomer) exhibited the largest adsorption capacity towards SA. Langmuir and Liu models could well fit the data of isothermal adsorption. The maximum adsorption capacity was estimated by the Langmuir and Liu models, which could reach out to an excellent value of 905.0 mg/g and 908.4 mg/g at 40 degrees C respectively. Furthermore, the pseudo-first-order rate equation could describe the kinetic data. The adsorption equilibrium of SA on IO PGMD-DETA-95 could be reached within 30-40 min. After five adsorption-desorption cycles, the excellent performance of IO PGMD-DETA-95 and the morphology were well retained.