Although P can deoxidize the Cu materials in continuous casting,it can greatly affect the quality of continuous casting Cu billets.The effects of P-Cu addition on the deoxidization and microstructure behavior as well as surface quality of Cu billets in up-drawing continuous casting were investigated.The results show that a certain P addition take a better deoxidization,meanwhile deteriorate the as-cast grain structure.With the P addition at a certain extent,the mechanical properties of the Cu billets can be improved and the working plasticity can be slightly decreased.With P addition more than 0.15%,the surface roughness is increased.The mechanical properties and processing performance of the billets is decreased with increase in P-Cu addition.It is difficult to take up-drawing,more even resulting in the occurrence of the drawing-out with the P addition more than 0.45%.So,proper P addition can better deoxidize the Cu materials and improve mechanical properties and machining performance.