Content of EPS affects not only the formation and stability of anammox granular sludge, but also the performance of reactor. To study the effect of influent water quality on the EPS content, sixteen SBR reactors with different total nitrogen concentrations, different IC/TN ratios and different COD/TN were operated and compared. Experimental results indicated that the content of EPS increased during the substrate utilization phase, but declined under the shortage phase. Specifically, the EPS content increased slighty with the increasing of total nitrogen concentration from 35 to 280 mg/L, however, it decreased significantly once the total nitrogen concentration exceeded 280 mg/L. With a IC/TN of 0.01-0.2, the content of EPS increased with a continuous input of inorganic carbon, but the inorganic carbon concentration had no significant effect on EPS content when IC/TN>0.2. Under the condition of COD/TN < 0.5, higher organic matter promoted EPS formation, but it inhibited EPS formation when COD/TN>0.5. Thus, long substrate utilization phase and the shortage phase should be avoided during the operation of anammox reactor, and the total nitrogen concentration should be maintained between 150-210 mg/L, IC/TN should be 0.1-0.2, COD /TN should be lower than 0.5.