It is possible to undergo a hair transplant without cutting the existing hair, depending on the technique used. Some hair transplant methods, such as FUE (Follicular Unit Extraction), involve extracting individual hair follicles from the donor area and transplanting them into the recipient area without the need for a linear incision or shaving of the hair. However, some trimming or shaving of the hair may still be necessary to ensure optimal results. It is important to consult with a qualified hair transplant specialist to determine the best technique for your individual needs and goals.