Corn silage has become an indispensable basic diet for ruminants due to its rich nutrients,good palatability,longer storage time,etc.The quality of silage directly affects the performance of ruminants.Near-infrared spectroscopy is widely used in the detection of silage quality because of its fast,accurate and non-destructive characteristics.Based on the index of whole-plant corn silage quality grading index(CSQS),this paper described the application of near-infrared spectroscopy to construct the prediction model of nutritional indexes,fermentation indexes and safety indexes of corn silage,and its key factors affecting the model construction,which was aimed at establishing a near-infrared.The aim was to provide a reference basis for the establishment of near-infrared prediction models of nutrient parameters for forage.