Abstract: The technical features of 321 stainless steel produced by steekle mill were introduced in this paper,including its alloying design,process control and mechanical properties.Morphology of the inclusions and the surface defects of the steel were analyzed by OM and SEM.The results showed that the 321 stainless steel exhibits excellent mechanical property and good surface quality.The main surface defect is linear scale,which is caused by the mass clustering of TiN grains in the continuously cast bloom.In order to effectively improve the surface quality of the steel,some measures can be taken,including controlling contents of elements such as Ti,Al,N,and O and degree of superheat during casting,and setting reasonable parameters of argon stirring in LF.