In order to study the purifying effect of combined ecological floating bed constructed by plants and artificial medium on the aquaculture wastewater, a combined ecological floating bed in pond was established by hanging the bio-ceramic matrix under the roots of Pistia stratiotes. Results showed that the removal rates of combined ecological floating bed for total nitrogen(TN),NH₄⁺-N, NO₂^--N, total phosphorus (TP), chemical oxygen demand(COD) were 52.38%, 77.78%, 81.97%, 67.57% and 43.98% respectively, which were significantly higher than the removal rates by single plant control or single matrix control (P<0.05). The concentration of TN and TP matched the Class Ⅰ standard of the waste water of freshwater fish pond after being purified by combined ecological floating bed, and the concentration of ammonia and nitrite decreased to below 0.15 mg/L and 0.02 mg/L respectively. The results also showed that the synergism of plant absorbing, matrix adsorption and microorganism enhanced the pollutant removal efficiency of floating bed and reasonable biological combination played a positive role in promoting purification effect on culturing wastewater by floating bed. This study provided technical support for building combined ecological floating bed proper for culturing wastewater purification.