Adsorption of Reactive Yellow 176 onto zeolite in a fixed-bed column system was investigated. To increase the adsorption capacity, we modified the surface of natural zeolite with a cationic surfactant (HTAB). The adsorption tests consisted of the modification of zeolite with HTAB followed by the dye removal in the column. The zeolite that was modified at 3 g/L HTAB concentration showed the best performance in adsorbing the yellow dye. The column with a 3 cm diameter and different bed heights of 25, 35, and 50 cm treated 24, 36, and 66 L at the breakthrough point, respectively, for 50 mg/L Reactive Yellow 176 dye solution at a flow rate of 0.050 L/min. The bed depth service time (BDST) model proved to be effective in the comparison of column variables. The minimum bed height, the adsorption rate constant, and the adsorption capacity of the HTAB modified zeolite for yellow dye removal were found to be 12.02 cm, 6.432 x 10(-3) L/(mg h), and 12.05 g/L, respectively. Color removal efficiencies of the simulated and real textile wastewaters were evaluated and adsorption capacity in the simulated textile wastewater and the real textile wastewater showed 25 and 62% decrease compared to the yellow dye solution. The column regeneration was also evaluated using a solution consisting of 30 g/L NaCl and 1.5 g/L NaOH with a pH value of 12 at 25 cm bed height with a flow rate of 0.050 L/min at temperatures 30 and 60 degrees C. Desorption efficiency increased from 23 to 90.6% with the increase in temperature from 30 to 60 degrees C.