The invention discloses a method for real-time 
fluorescence quantification PCR (qPCR) detection of denitrifying microorganisms in 
aquaculture environment sediments, and belongs to the technical field of environmental 
microbial ecology. The method comprises the following contents: metagenome 
DNA extraction and concentration determination of 
sediment samples in various stations, PCR amplification of nirK and nirS genes, construction of a standard 
plasmid, preparation of a 
standard curve, qPCR amplification and calculation of the number of denitrifying microorganisms in the samples according to a qPCR result in accordance with the 
standard curve. The method disclosed by the invention can be used for determining the number of the denitrifying microorganisms in an 
aquaculture environment through quantitative analysis on two genes, namely nirK and nirS, so as to overcome the shortcoming that 16S rRNA 
gene cannot be used in the quantification of the denitrifying microorganisms as well as the shortcoming that the prior art, which focuses on some functional 
gene only, is incomplete in quantification; and the provided method for detecting the number of the denitrifying microorganisms in the 
aquaculture environment is good in specificity, high in 
repeatability and high in accuracy. According to the method disclosed by the invention, logarithm values of nirK and nirS 
gene copy numbers keep a good 
linear relation with Ct value of a 
luminescence threshold, and the regression coefficient of the 
standard curve is above 0.99.