Abstract: Under waterlogged incubation conditions, the nitrogen mineralization of two different sediments and a general Beijing’s soil were investigated with the method of the intermittent leaching, besides their nitrogen mineralization parameters (K, n) and the prediction equation were gained. The results indicated that their mineralization potential was in the order: Houhai sediment> Chaoyangqu soil > Huankeyuan sediment. The rates of the N mineralization before the 11 incubation day are promptly augmenting to the maximal, and then the rates are gradually falling, at the end of incubation theirs are close to zero. The flood tide of nitrogen mineralization rates of HH sediment appeared earlier than HK and TR. The flood tide of ammonium in the N mineralization process appeared in the 11 day of leaching time, and the N mineralization quantity gradually got into a windless state. In the same period the N mineralization quantity of HH was further more than HK and TR. The content of organic matter、the total nitrogen and the fixed ammonium in the different treatments and levels at the end of incubation were lessened, and a few of N mineralization quantity came from the release of the fixed ammonium. But because the proportion was small, the part of the fixed ammonium could be ignored.