Abstract: Skull bone is one of the most important parts in the human's body,which protects and supports the brain tissues. Nowadays,due to many various reasons,a lot of people suffer from the skull bone defects,which not only affect the appearance,but also may cause brain damages. How to repair the skull bones for people effectively has become an international hot topic. At present,doctors diagnose the state of the bone defect illness mainly depending on observing the CT images of patients,and make the repair model by hand. It mainly depends on the technique and experience of the doctors. In order to solve this problem,this paper focuses on using the interactive technology to make the skull repair procedure efficient. During this process,we used B-Spline to repair some typical slices or each slice of the CT images,construct the restoration that fits the skull surface and then transfer it as a file in specific format to a machine based on technology of computer aided design and computer aided manufacture to produce a real restoration. This method can shorten the time of operation,reduce the risk of operation,and produce a suitable repair result for patients.