Abstract: It is is studied that that Bio-fertilizer degradation degree to Douhuanglong useing the manual simulation method. The results shown shows that the difference of plant height and blade age are not bigsignificant of difference treatments. Tillering of per plant of 17.781.20μg/kg treatments is more aboutabout one times than 0~8.890.4μg/kg treatments. Bio-fertilizer affects growth and the accumulation doing matter of the paddy rice, matter accumulation is the quickest and the root quantity is the most when 30kg/hm2 Bio-fertilizer is used in one hectare. The paddy rice maturation period defers about 10 day when Douhuanglong's residual amounts is 17.781.2μg/kg, The paddy rice maturation period of the treatments no using Bio-fertilizer is later 2~3 days than the treatments using Bio-fertilizer. The paddy rice output of the treats treatments using 30kg/hm2 is maximal when residual amounts of Douhuanglong are identical. The output of paddy rice reduces with residual amounts of Douhuanglong increasing, reduction of output is no more than 20% when residual amounts of Douhuanglong areis 0 ~ 8.89 & micro0.4μg/kg; reduction of output is about 50% when residual amounts of Douhuanglong is 1.2μg/kg.