Abstract: The causes for cracking of the large-sized centri fugally-cast composite sizing roll are analyzed, involving such factors as structure design, production characteristics and centrifugal casting process, etc. And the stress as resulting from the centrifugal casting process and the distribution thereof are measured with the magnetic measurement method. Based on the analysis result, it is proposed to solve the cracking problem of the said sizing roll by means of improving structure design of the roll, regulating the roll operation procedure, control quality of spheroidization and inoculation, enhancing the roll inner layer strength, and reducing casting stress.