Oral and maxillofacial surgery plays an important role in improving patients' oral health and appearance. However, a successful operation must have accurate preoperative evaluation and surgical planning to improve the safety and effectiveness of the operation. The purpose of this paper is to analyze the preoperative evaluation and surgical planning of patients with oral and maxillofacial surgery, and to explore the correlation between the two. By reviewing the key elements of preoperative evaluation, this paper analyzes the key steps of preoperative planning, and puts forward the comprehensive treatment methods of patients with oral and maxillofacial surgery, aiming to provide some reference for improving the practice of oral and maxillofacial surgery.