In this study, discharged effluent from 24 sites which will be subjected to enforced whole effluent toxicity legal standard since 2016 where 4 kinds of industrial categories, plating facilities etc. analysed whole effluent toxicity characteristics by industrial classification. Main research topics include evaluated the operational status of whole effluent toxicity tests, determine the cause and wastewater treatment facilities, which were obtained based on the following conclusions. The sites exceeded whole effluent toxicity legal standard at the effluent salinity was high and the main reason of exceed caused by salt. The sector showed the largest deviation between the discharge facilities within the same sector is a plating facilities and the result of analysis of the effluent salinity, conductivity, total dissolved solids were high at the inorganic chemical manufacturing facility.