Postoperative pain in elderly patients with lung cancer after thoracoscopic surgery is still an important factor affecting the prognosis of patients. In this study, 200 elderly patients with lung cancer who were positive and planned to undergo video-assisted thoracoscopic surgery were randomly divided into four groups: control group, SAPB (serratus anterior plane block) group, Nalbuphine group and Nalbuphine + SAPB group. The effects of drugs and nerve block on the perioperative indexes of elderly patients were observed. The results showed that ① The VAS and SAS scores of postoperative analgesia in the Nalbuphine + SAPB group were lower than those in the single group and the control group. ② The postoperative spontaneous respiratory recovery time, extubation time, resuscitation room stay time, extubation cough, restlessness and respiratory depression in the Nalbuphine + SAPB group were lower than those in the single group and the control group. ③ The heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and blood oxygen saturation (SpO2) of patients in Nalbuphine + SAPB group before induction, T2 after intubation, T3 before skin incision, T4 after skin incision, T5 after chest closure and T6 after extubation were lower than those in single group and control group. Therefore, this study concluded that Nabufine combined with SAPB can make the vital signs of intraoperative patients more stable, which is worthy of clinical promotion.