Aiming at the problems of low sensitivity and poor selectivity of spectrophotometry and titration in the analysis of hydroxylamine nitrate content in energetic material production wastewater， a high sensitivity analysis method based on gas chromatography tandem mass spectrometry （GC-MS） was developed for the determination of trace hydroxylamine nitrate in water. Through acetone derivatization， hydroxylamine nitrate reacted with acetone to produce acetone oxime which was easy to be tested by gas chromatography. The derivatization conditions and GC-MS parameters were optimized， and N， N-dimethylnitrosamine （NDMA） was used as the internal standard for quantitative analysis. The results showed that the linear relationship of hydroxylamine nitrate in the linear range （R²>0.999） was good， the detection limits was 0.015 mg·L^-1， the recovery rate was 95%-108%， and the relative standard deviation was 3.6%-5.7%. This method has been successfully applied to the analysis of industrial waste water. It has the advantages of simple operation， high sensitivity and strong anti-interference ability. It provides an efficient and accurate analytical method for the monitoring of hydroxylamine nitrate in environmental water.