Abstract:[Objective] To investigate the effects of Na2SeO3 and Epichloë sp. on Festuca sinensis, we studied the growth indexes and metabolic compounds. [Methods] By using gas chromatography-mass spectrometer, we detected the metabolic compounds of the shoots and roots of F. sinensis two geographical populations with and without Epichloë endophyte, and metabolite differences were determined among treatments using LSD test. [Results] Geographical populations Haibei (HB) and Yushu (YS) respectively had 206 metabolites and 205 metabolites. There were significant differences in metabolites between shoots and roots. Geographical population HB shoots, HB roots, YS shoots and YS roots, respectively showed 27, 42, 40 and 33 marked metabolites using LSD (P<0.001). These marked metabolites were some nitrogen compounds, carbohydrates and organic acids. 9, 8, 5 and 14 common marked metabolites were respectively found between HB shoots and roots, between YS shoots and roots, between HB and YS shoots, and between HB and YS roots. Epichloë endophyte caused a highly significant increase in tyrose for geographical population HB shoots and roots (P<0.001). Selenium induced highly significant increases in α-ketoisocaproic acid in HB E+ and E-shoots and roots (P<0.001). There were highly significant increases of aspartic acid for HB shoots and roots by interaction of the Se and Epichloë endophyte (P<0.001). In addition, selenium treatment highly significantly increased α-ketoisocaproic acid and acetol for shoots and roots in geographical population YS E+ and E-(P<0.001). [Conclusion] There were significant differences in metabolites of the shoots and roots of two geographical populations. Epichloë endophyte infection and/or selenium treatment can increase the concentrations of some compounds.