To discuss the variations in carbon di-xide emission rate between reed and cotton fields of estuary wetland in temperate zone,we analyzed the differences of soil respiration rate between cotton community and reed community.The experiment was held in Autumn,10,6,2012,and the experiment field lay in Yellow River delta,which is the youngest wetland in temperate area. The soil respiration rate was measured by Li-8100(produced by USA),the data of soil temperature and moisture were also recorded by the instrument of Li-8100,atmospheric temperature and relative humidity were monitored synchronously.The results showed that the daily changing curves of soil respiratory rate of both cotton community and reed community were asymmetric unimodal,the maximum rate appeared at 12:00-14:00,and the minimum rate was observed at 6:00-8:00.However, the mean respiratory rate of the two communities showed great difference,the average respiratory rate of cotton community and reed community were 0.927mumol/(m~2·s)and 0.725mumol/(m~2·s),respectively.These phenomena indicated that the cultivated wetland can lead to the increase in carbon emission and contributes to the global warming.The correlation analysis disclosed that soil temperature and atmospheric humidity were the main factors influencing soil respiration of the two communities.In detail, soil temperature was the primary environmental factor influencing soil respiration of reed community,and the atmospheric humidity influenced soil respiration of cotton community mainly.The experiment data can be used as the parameters of estuary wetland ecosystem carbon cycle.