Abstract: The authors had studied ultraviolet absorption spectrum character of organic contaminants in sewage samples collected from bathing wastewater,domestic wastewater,along with their effluents of bio-treating installation.The authors put forward that ultraviolet absorption spectrum parameter of a dissolved organic contaminants in sewage correlates with the traditional comprehensive index of organic contaminant,such as Chemical Oxygen Demand(COD) and Total Organic Carbon(TOC).The study can be used for reference of on line wastewater quality measurement.The results are that there are good correlation between the ultraviolet absorption parameters including UV absorption at a UV wavelength of 254 nm(A₂₅₄) and an integral UV absorption from 226 to 400 nm of UV wavelength ranges(A_226,400) and COD or TOC.Then preferable correlation is in A_226,400 and TOC,which shows comprehensively the characters of organic contamination in sewage.Futhermore,testing A_226,400 was quicker,easier and no consumption of chemical reagent.It was an environmental water-quality analysis technique and can be a substitute for traditional comprehensive index of organic contaminant in sewage to a certain extent.