The size of detects in scalp for which primary wound closure can be applied is limited. Cases with a scalp defect for which primary wound closure is difficult to perform are frequently seen. In these cases, an attempt is made to close the wound by extending the margin of an incision produced by extensive subgaleal undermining or galeal incisions. However, its effectiveness is limited. We performed in such cases intra-operative scalp expansion with a tissue expander for primary wound closure, and this technique has yielded good results. A case with craniosynostosis and five cases with cranioplasty received this procedure. Four of these cases had a previous history of undergoing surgery for carvarial bone defect three to five times from the same incision. The scalp at the carvarial bone defect had a scar and was atrophic with great depression. It was expected that the expansion of cranium resulting from cranioplasty would make it difficult to perform primary wound closure. During the surgery, a tissue expander was placed subgaleally in an osseous area prior to the bone operation, and intermittent air expansion was carried out for 20 to 30 minutes by means of air inflation and deflation to expand the scalp. In all of these cases little tension was generated by the wound closure despite the lapse of time during the bone operation. In consequence, primary wound closure was accomplished easily, and the reliable closure of the galea made it possible to prevent the scar widening. This is a simple and easy technique combining primary wound closure of the scalp with intra-operative scalp expansion. We believe that the technique should be considered for cases for whom primary closure of compression deformity is difficult or in whom there is a wound at the carvarial reconstruction site. The technique and typical cases are reported.