Objective?To investigate the application effect of ultrasound guided paravertebral nerve block combined with psychological guidance in elderly patients with thoracoscopic lung cancer radical surgery and its influence on cognitive function. Methods?A total of 68 elderly patients with thoracoscopic radical resection of lung cancer admitted to Huaiyin Hospital of Huai 'an City from January 2018 to May 2020 were selected as the research subjects，and were divided into control group and observation group by random number table method，with 34 cases ineach group. The control group was treated with ultrasonic-guided paravertinal nerve block，and the observationgroup was combined with psychological guidance on the basis of the control group. After 7 days of nursing，the effect of patients was evaluated. The visual analog pain（VAS）score，simple mental state scale（MMSE）score，awakening time and complication rate were compared between the two groups. Results?The VAS，MMSE scores，spontaneous breathing recovery and eye opening time of the observation group were lower（shorter）than those of the control group（P ＜ 0.05）；the incidence of nausea and vomiting，respiratory depression，blood pressure fluctuation，dysphagia，dizziness and drowsiness in the two groups were not statistically significant（P ＞ 0.05）.Conclusion?Ultrasound guided paravertebral nerve block combined with psychological guidance in elderly patients with thoracoscopic lung cancer radical surgery can reduce the pain of patients，improve the cognitive function of patients，help to shorten the recovery time of patients，without increasing the incidence of complications，which is worthy of promotion and application