The amide metabolites ofPhomopsis sp. ZZF08 from the South China Sea were isolated and purified by chromatography. Their structures were determined by MS, NMR, X-ray diffraction data and comparison with the literature data. Cytotoxicity in vitro was performed by tetrazolium (MTT) assay. Twelve amide compounds were isolated, which were viridicatol (1), cytochalasin H (2), cytochalasin IV (3), glucosylceramide (4), ceramide (5), allantoin (6), thymine (7), pyridine (8), cyclo-(Leu-Gly) (9), cyclo- (Leu Ala) (10), cyclo- (Phe Gly) (11), and cyclo- (Phe-Ala) (12). Compounds 1,2,3,4 and 5 were isolated firstly from Phomopsis sp. collected from the mangrove bark of the Zhanjiang. In our cytotoxicity assays, compounds 2 and 3 exhibited strong cytotoxicity toward KB cells and KBv200 cells.