In modern architecture,the architectural modeling is becoming more and more novel,and the structure is also becoming more and more complex. Therefore,the traditional reinforced concrete structure can not meet the special structural requirements,this can only be achieved by steel structure engineering,and the curved torsion surface molding members are widely used in steel structure engineering. The fabrication and precision control measures of steel structure curved torsion trusses are discussed from the aspects of deepening design of steel structure,weld design,parts nesting and forming, member assembly,member welding and forming precision detection,which provides a reliable reference scheme for the processing and fabrication of similar steel members.