[Objective]To analyze the changes of soil nutrients after temperature increase,in order to provide data support for responses to global warming in the future.[Methods]The brown soil of cultivated land in North China plain was taken as study material.Sedimentation Siphon method was used to study the composition of three granular organic-inorganic complexes and the variation of organic carbon and total nitrogen in soil under increasing temperature.[Results]The distribution of soil organic and inorganic complexes showed no significantly change under the condition of increasing temperature.Organic carbon content increased while total nitrogen content decreased.In terms of different grain levels,the content of organic carbon in all three grain grades increased,while the content of total nitrogen only increased in some small soil grain.No significant change was fond in the content of total nitrogen in sand grains.The soil carbon nitrogen ratio was relatively stable.The distribution of organic carbon tended to shift to large grain size,while the distribution of total nitrogen showed no obvious pattern.[Conclusion]Temperature increase accelerated the decomposition of organic matter,and increased the content of soil organic carbon,especially in smaller grain size.In contrast, the total nitrogen content decreased as a result of anti-mineralization,but it showed a relative increase trend compared with the control group.