The invention discloses a nested PCR (
polymerase chain reaction) kit for detecting duck-
manure pollution in a 
water body and a detection method thereof, and belongs to the field of the detection of 
pollution in water bodies. The nested PCR kit for detecting the duck-
manure pollution in the 
water body comprises two pairs of nested PCR primers, dNTP (
deoxyribonucleoside triphosphate), a PCR buffer, a 
Taq polymerase, a Mg<2+> solution and ddH2O (double 
distilled water). Two rounds of PCR amplification are used by a nested 
PCR method. The detection method comprises the following steps of extracting 
a DNA (deoxyribonucleic acid) in a to-be-detected 
water sample, and carrying out a first round of PCR amplification by using the 
DNA in the to-be-detected 
water sample as a template, wherein the primers are an SDF (stroma derived factor) and SDR (short-chain 
dehydrogenase  / 
reductase); after a first reaction is terminated, carrying out a second round of PCR amplification by using a product of the first round of PCR amplification as a template, wherein the primers are an NDF (
neutral detergent fiber)and NDR, and after a second reaction is terminated, detecting the existence of a 158bp strip, which shows that the 
water body is subjected to the duck-
manure pollution, through 
agarose gel electrophoresis. According to the method, the detection sensitivity is greatly increased through nested PCR amplification; a little duck-manure pollution which exists in water can be detected; moreover, the method has a favorable specificity, and can be directly applied to the detection and the preventive treatment work of fecal pollution in the water body.