To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment,943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary treatments,secondary effluents and final effluents (effluents of advanced treatments),which were collected from seven full-scale municipal wastewater treatment plants (MWTPs) in China,were examined by gas chromatography-mass spectrometry (GC-MS) coupled with an automated identification and quantification system with a database (AIQS-DB).In total,196 and 145 chemicals were detected in secondary and final effluents,respectively.The majority of the total concentrations (average removal efficiency,87.0％±5.9％) of the micropollutants were removed during secondary treatments.However,advanced treatments achieved different micropollutant removal extents from secondary effluents depending on the different treatment processes employed.Highly variable removal efflciencies of total concentrations (32.7％-99.3％) were observed among the different advanced processes.Among them,ozonation-based processes could remove 70.0％-80.9％ of the total concentrations of studied micropollutants.The potentially harmful micropollutants,based on their detection frequency and concentration in secondary and final effluents,were polycyclic aromatic hydrocarbons (PAHs) (2-methylnaphthalene,fluoranthene,pyrene,naphthalene and phenanthrene),phosphorus flame retardants (tributyl phosphate (TBP),tris(2-chloroethyl) phosphate (TCEP) and tris(1,3-dichloro-2-propyl) phosphate (TDCP)),phthalates (bis(2-ethylhexyl) phthalate (DEHP)),benzothiazoles (benzothiazole,2-(methylthio)-benzothiazol,and 2(3H)-benzothiazolone) and phenol.This study indicated that the presence of considerable amounts of micropollutants in secondary effluent creates the need for suitable advanced treatment before their reuse.