Abstract: Simulated indoor incubation experiment was carried out to explore the dynamics of Allantoin(All) in different manures. The results show that All from different manures is quickly degraded in soil, and the degradation rate and degradation percentage are significantly different for different antibiotics with different concentrations. At day of 180 the highest All degradation percentages of chicken feces and pig feces reach to 95.59% and 90.83% respectively. The degradation percentage is negatively correlated with the amount of manures used and positively correlated with incubation time (v=A+B lnt). Microbiological decomposing plays an important role in the process of degradation, and accounted for about 78%, therefore, the concentration of All is declined through microbiological degradation and others, but it may have the risk of environmental at a short time after the manures entering the soil.