Abstract: For the characteristics of wastewater in steel industry，the paper analyzed the current wastewater pollution control measures of mainly processes and the whole plant in steel industry，stressed the major processes，water quality and main problems of the two levels reverse osmosis． Through the site survey in large steel groups，taking TISCO's reverse osmosis and evaporation and crystallization process as an example，the technical feasibility of zero discharge of wastewater was realized in steel industry． This technology could resolve the problem of discharging the brine．