Adsorption is an effective and reliable method to recover phosphorus (P) from sewages. Extracellular polymeric substances (EPS) and agarose are common polysaccharides bioresources, and their carboxylic and phenolic hydroxyl groups can directly adsorb P via ion exchange and hydrogen bonding mechanisms. Here, we designed EPS-based and Fe-modified hydrogels (agarose (AG)- and agarose-humic (AH)- based hydrogels) for P recovery. The results showed that AG and AH hydrogels could adsorb 33.9 and 67.7 mg P g−1, respectively. Both as-developed hydrogels showed > 75% of the maximal adsorption capacity in the tested pH conditions (3−10). Coexisting anions (i.e., SO42-, NO3-, and CO32-) did not significantly affect the adsorption performance, except for CO32- which inhibited the process. Intraparticle diffusion controlled the adsorption process. After adsorption, large amounts of FePO4 and Fe2(HPO4)3 were generated in the hydrogels, confirming that ligand exchange was the major driving force. Display omitted •EPS-based hydrogels are made from agarose and humic acid.•EPS-based hydrogel appeared to have excellent phosphorus adsorption performance.•Ligand exchange is the major driving force for hydrogels to trap phosphate.