Abstract:A total of 18 strains of marine endophytic fungi were fermented by three fermentation media with significantly different carbon sources, nitrogen sources and growth factors, which was gotten from 54 fermentation products. These 54 fermentation products were evaluated through chemical screening and bioactivity screening. The ethyl acetate extract of 18 strains of marine endophytic fungus was screened by HPLC, antioxidant activity in vitro and antibacterial activits. Ethyl acetate extract (10 mg/mL) of the strain 150103 (medium 1) could inhibit bacillus subtilis and Staphylococcus aureus effectively. The diameter of inhibition zone is 12 mm and 11 mm respectively. It couldn’t inhibit Escherichia coli evidently. It could remove more than 90% of DPPH free radicals. According to the HPLC results, extract of the Strain 150103 (medium 1) is rich of secondary metabolites. The Strain 150103 (medium 1) is rich of secondary metabolites, has strong antibacterial and antioxidant activity in vitro, and deserves deep research.