Abstract: Elaborated in the paper is how the inclusions in the steel for tube-rolling are controlled by Pangang Group Chengdu Steel and Vanadium Co.,Ltd.Comparatively analzyed are the results of two calcium treatment processes for denaturization of Al₂O₃ and MnS inclusions in the aluminium-killed 30CrMo steel for tube-rolling.Based on the analysis result,it is concluded that neither of the said two processes is capable of fully denaturizing both oxide and sulfide in the steel,and thus,only by means of increasing the effective content of calcium in the steel,can the purpose of full denaturization be met.