The feasibility of using zeolite clinoptilolite to filter nitrate and phosphate pollutants and salt from agricultural drainage-water was studied in the current research. Significant pollutant absorption parameters, such as adsorbent particle size, pollutant concentration, salinity, temperature, retention time, pH, and adsorbent concentration, were optimized in the batch condition. After the optimization of parameters, adsorption experiments were conducted on an experimental model, similar to subsurface drainage systems that are applied in farms. Adsorption experiments were carried out at optimized parameter levels on four models, namely a reference model (D0), a model with adsorbent around drains (D1), a model with adsorbent around plant roots (D2), and a model with adsorbent on the soil surface (D3); they were fed with untreated drainage-water from south Khuzestan farms during the fertilization season. The results were suggestive of a 63 percent Nitrate-removal efficiency, 39 percent Phosphate-removal efficiency and 79 percent salt-removal efficiency made possible by 30 g.L-1 of 1000 µm adsorbent particles, for a pH of 5, initial pollutant concentration of 80 mg.L-1 nitrate and 10 mg.L-1 phosphate, a 12 dS/m salinity, 90-minute retention time, and 50 °C ambient temperature. These parameter levels enabled nitrate, phosphate, and salt-removal efficiencies of 59.72 percent, 29.28 percent, and 77.47 percent respectively, in the model with clinoptilolite adsorbents around the drains (D1).