Mangrove-derived endophytic fungi are important and promising resources for the novel natural products discovery and have attracted much attention of natural product chemists. A strain of fungus Aspergillus sp. HS02 was isolated from the leaf of the mangrove plant Sonneratia hainanensis endemic in Hainan Island. Fermentation of this fungus was conducted in liquid malt extract medium (MEA). From the ethyl acetate extract of the fermentation broth, one major component 1 was isolated and purified by normal phase, reversed-phase silica gel and sephadex LH20 column chromatography. The structure of compound 1 was identified as a new indole alkaloid by high resolution electrospray ionization mass spectroscopy, one-dimensional nuclear magnetic resonance spectroscopy, heteronuclear single quantum correlation, heteronuclear multiple bond correlation and 1H-1H correlated spectroscopy. It was named as quinadoline C. The anti-fungi activity of quinado line C against two agricultural pathogenic fungi was evaluated in vitro by filter paper disc diffusion method. © 2018, Science Press. All right reserved.