Bisphenol　A　(BPA)　and　nonylphenol　(NP)　are　well-known　endocrine-disrupting　chemicals　(EDCs)　present　in　the　aquatic　environment,　but　little　is　known　about　their　oxidative　stress　effects　on　fish　embryos.　In　the　present　study,　we　examined　the　oxidative　stress　indices　and　antioxidant　parameters　of　zebrafish　embryos　after　a　short-term　exposure　to　various　concentrations　of　BPA,　NP,　and　their　mixture　(BPA-NP)　for　4h　postfertilization　(hpf)　to　168　hpf.　Exposure　to　the　chemicals　was　found　to　enhance　the　production　of　hydroxyl　radicals　and　lipid　peroxidation　in　a　concentration-dependent　manner.　The　content　of　total　glutathione　(TG),　reduced　glutathione　(GSH).　and　oxidized　glutathione　(GSSH),　as　well　as　the　activity　of　antioxidant　enzymes　including　catalase,　superoxide　dismutase,　glutathione　peroxidase,　glutathione　reductase,　and　glutathione-S-transferase　were　all　significantly　inhibited　after　exposure　to　BPA,　NP,　and　BPA-NP,　indicating　the　occurrence　of　oxidative　stress.　Coexposure　to　BPA-NP　resulted　in　an　additive　effect　on　some　antioxidant　parameters.　In　addition,　the　alkaline　phosphatase　activity　was　also　significantly　inhibited　after　exposure　to　BPA,　NP,　and　their　mixtures.　Our　results　demonstrated　that　BPA,　NP,　and　BPA-NP　in　aquatic　systems　can　affect　antioxidant　responses　in　zebrafish　embryos.　Environ.　Toxicol.　Chem.　2011;30:2335-2341.　(C)　2011　SETAC