Recently, thin strip casting technology has been widely used in the development and productionof silicon steel. Strip casting process characterized by sub-rapid solidification of molten steel(cooling rate: 102-104℃/s) can refine the solidification structure and reduce segregation. The mainadvantage of the technology is short process, which can simplify the complicated secondarytreatment process, and enable the production of high-quality silicon steel strip with low-costpossible [1]. However, the cracks distributing on the surface or interior of the high-silicon steel striphave a significant influence on the quality of strip. The cracks influence the subsequent productionand application of high silicon steel by increasing the movement resistance of magnetic domainwall and iron loss. Therefore, inhibition formation of crack during strip casting is very essential toimprove the quality of high silicon steel. Currently, studies on the crack formation mechanism oflow-carbon steel and stainless steel during the strip casting were reported [2, 3]. However, very fewstudies were made on the crack formation mechanism of high silicon steel fabricated by stripcasting.In present study, cracks forming during strip casting of high silicon steel were investigated, andthe microstructure and fracture surface in the vicinity of crack were observed and analyzed. Thefactors leading to the crack and crack formation mechanism involved in the strip casting werestudied. The modified approaches were further proposed toward to twin-roll strip casting process,which were expected to provide fundamental theory for developing silicon steel with excellentperformance.