Abstract: In order to offer more scientific and economic fertilizing method to agriculture, the effects of three different kinds of organic fertilizers, normal organic fertilizer (T1), carbon organic fertilizer (T2) and full nutrients organic fertilizer (T3) on the growth and economic benefit of Brassica napus L. were studied in this experiment. The results showed that: the dry weight, fresh weight and chlorophyll content of Brassica napus L. increased. Compared with other treatments, T2 treatment was the highest and the difference was extremely significant. Pn diurnal variation of Brassica napus L. leaf under different treatments were bimodal curve and “midday depression” phenomenon was not obvious. Compared with the CK, Pn of the two peaks under the three treatments all increased. T2 treatment were both the highest, they increased by 32.26% and 32.26% than that of CK. All organic fertilizer treatments improved output values, and the T3 treatment was the largest, the newly added value was 3156.75 yuan per hectare. From the rate of newly added value/newly added fertilization cost, we could see that it had obviously appreciation under T2 treatment and T3 treatment, and newly added value could reach 10.60 yuan and 25.51 yuan respectively by 1 yuan investment, therefore, both the two kinds of organic fertilizers on the Brassica napus L. cultivation fertilization method was feasible and economical.