The study aims to examine the effect of adding duck manure with different doses on the nitrogen and phosphor uptake of Lemna minor. Experimental design used was Completely Randomized Design (CRD) with 5 treatments and 4 replications. Treatment applied were P1 = control, no duck manure excrement; P2 = addition of 5 g/l of duck manure; P3 = addition of 10 g/l of duck manure; P4 = addition of 15 g/l of duck manure; P5 = addition of 20 g/l duck manure. Data were analyzed with Analysis of Variance and if there was a significant treatment effect (p <0.05) data were continue analyzed by Duncan\u27s multiple range test at the level of 5% and Orthogonal Polynomial test. The results showed that the addition of duck manure was able to increase uptake of nitrogen and phosphor uptake significantly (p<0.05). The highest nitrogen uptake achieved in the addition of duck manure as much as 19.625 g/l while the uptake of phosphor at 13.12 g/l. The highest nitrogen and phosphor utilization efficiency achieved in the addition of duck manure 20 g/l of 2.4380% and 15 g / l of 8.6232%