A full-scale investigation and analysis of MGP(Manufacture Gas from Petroleum)-Wastewater was carried out in this study. It's the first time that this paper publicizes the wastewater's general data, pretreatment method of GC/MS analysis and compositions of toxic organic compounds. The concentrtion of wastewater's CODCg, BOD5, phenolic, N-NH4+ and extractive-organic is: 400 mg.L(-1)-600 mg.L-1, 60 mg.L(-1)-80 mg.L-1, 20 mg.L(-1)-30 mg.L-1, 60 mg.L(-1)-80 mg.L-1 and 170 mg.L(-1)-200 mg.L-1 respectively. There are 79 kinds of aromatic compounds were detected by GC/MS, the total concentration of influent and effluent is 140.79 mg.L-1 and 129.11 mg.L-1 respectively. The data approved that MGP-wastewater is toxic and difficult for bio-treatment.