In order to explore the effect of nano-zero-valent iron (nZVI) on the storage and in-situ recovery of aerobic granular sludge (AGS) at room temperature, the sludge-water mixture (mass concentration of mixed liquid suspended solid 7.5 g/L) in a 52.0 L sequencing batch reactor was used as the original AGS, and nZVI was added to 1 L of the original AGS to construct a storage system. Based on the 60 d storage experiment, 6 d recovery experiment and organic carbon source (COD) batch experiment, the effects of nZVI addition on the physicochemical properties and denitrification performance of AGS during storage and recovery were investigated, and the changes of nitrification and denitrification were analyzed. The results showed that in the 60 d storage experiment, the amount of nZVI had little effect on the particle shape of AGS before and after storage. The color of all AGS particles became black in different degrees, and the extracellular polymer content, ammonia oxidation rate and nitrate denitrification rate decreased significantly. In the 6-day recovery experiment, most of the AGS particles returned to yellow after the recovery period. The specific oxygen consumption rate and extracellular polymer content of AGS in S2 and S3 with nZVI addition of 1 and 10 g were significantly reduced. The addition of nZVI had no significant effect on the sedimentation of the particles, but had a significant inhibitory effect on the biological activity of AGS, and the inhibitory effect was positively correlated with the amount of nZVI added. The denitrification performance of S1 with 0 g nZVI was the best, and the removal rates of ammonia nitrogen and total inorganic nitrogen reached 95.1% and 84.8% on the first and second days, respectively. S2 reached 93% and 81.3% on the 2nd and 3rd day, respectively. S3 reached 90% and 80.5% on the 4 th day, respectively. In the COD batch experiment, the nitrification reaction of S2 was not significantly different from that of S1, but the nitrite denitrification rate of S2 increased and the nitrate denitrification rate decreased. COD is the main electron donor in the denitrification process of nitrite nitrogen, and nZVI also provides some electrons to supply nitrite nitrogen denitrification, thus enhancing the denitrification rate of nitrite nitrogen. In the denitrification process of nitrate nitrogen, nZVI reacts with COD and lacks the electrons required by the system, thus reducing the denitrification rate of nitrate nitrogen.