Using Fe (NO3)3 as modifying agent, a new porous environmental ceramic filter is modified at surface to pre-treat slightly-polluted water. It can effectively reduce organic substances in subsequent processes, thus enhance the quality of water output. The iron oxide / modified ceramic filter media was manufactured by heating vaporization, and the optimal modification conditions were as follows: pH value is seven, Fe (NO3)3 density is 2mol/L, and roasting temperature is 550 centigrade. Compared with plain ceramic filter media, the removal rate of COD was enhanced six to eight times. The surface morphology of filter media was inspected by SEM, which showed that the iron oxide film, being fine particles, was attached to the ceramic filter. This is beneficial for enhancing adsorption capability. The matter species of iron oxide film were analyzed by XRD, result showed that it contains α-Fe2O3 and α-FeOOH, which is helpful for adsorbing and removing organic substances in water.