The correlation relationship between soil biaomass nitrogen and mineralisable nitrogen was studied with field experiment and incubation experiments. The result showed: that correlation relationship between soil biaomass nitrogen and mineralisable nitrogen had weak correlation relation under field conditions; but there was significant linear correlation relationship between soil biaomass nitrogen and mineralisable nitrogen under waterlogged incubation conditions

nitrify incubation method and Standford short-term incubation method

and the correlation coefficients were over 0.767(p<0.001

n=12). The difference of results between field experiment and incubation experiments was relative with the difference between experiment conditions. The newly soil biaomass nitrogen was easily decomposable

but the old one was stable relatively.