For increasing utilizable efficiency and reusing concrete completely of waste concrete, the feast bility of using waste concxete for cement addition is studied through XRD patterns. The paper teed sepa- rately 10%，20% and 30% writes concrete to replace cament and test's the effect of two kinds of excita- nts. The experimental results shay that 42. 5 ordinary Portland canent can be producedwhen the admixing amount of waste concrete is less than 10% and 32. 5 ordinary Portland cement can be produced when the admixing anount of waste concxete is less than 20%.Excitant Na₂SiO₃ mixes is 1% appropriately and the excitant NaOH has no obvious effect.