Objective To look into the experience and feels of the family caregivers of brain tumor patients undergoing surgery. Methods The phenomenological methodology was used in the study. Eighteen family caregivers nursing brain tumor patients were selected as our target. Semi-structured interviews were performed to investigate their feelings and experience during the preoperative period. Result Three topics from our study were concluded: inappropriate emotional reaction, inexperience in the disease management and insufficiency in social support. Conclusion Medical staff and institutions should provide emotional, nursing technical support and professional knowledge for the caregivers so that they can improve their adaption ability and relieve the stress.