Abstract: The objective of this study was to screen functional lactic acid bacteria and investigate their effects on the fermentation quality and nutritional quality of Pennisetum ginanteum silage, thereby providing strain resources for the Pennisetum ginanteum silage fermentation. The growth and acid tolerance performance of different lactic acid bacteria strains were screened. Their inhibitory abilities against Escherichia coli, Staphylococcus aureus and Salmonella were assessed. Excellent lactic acid bacteria strains were obtained and used for the fermentation of Pennisetum ginanteum silage fermentation, and their effects on the silage of Pennisetum ginanteum silage fermentation were observed by measuring the nutritional quality and fermentation quality after fermentation. The results showed that the screened Lactobacillus plantarum strains FJAT54906 and FJAT54898, as well as Lactobacillus fermentum strain FJAT54908, have the characteristics of strong acid resistance, fast growth rate and acid production rate, and good antibacterial effect. Adding L. plantans FJAT54906 and FJAT54898 and L. fermentans FJAT54908 for the silage fermentation of Pennisetum ginanteum grass can increase the contents of crude protein and total sugar, reduce the content of crude fiber, and increase the content of amino acids. Based on the analysis of membership functions, the comprehensive nutritional value of the silage feed of different lactic acid bacteria was as follows: FJAT54908 group, FJAT54898 group, FJAT54906 group, CK group, from high to low.