Objective To explore the risk factors of sarcopenia in patients with lung cancer and construct its nomograph prediction model. Method From September 2020 to September 2022 96 patients with lung cancer admitted to Huai 'an Second People's Hospital special needs ward were regarded as the study subjects the clinical data and laboratory indicators of patients were recorded bioelectrical impedance test was applied to detect human body composition according to the criteria established by AWGSOP the patients were grouped into two groups myopenia group 52 cases in the concurrent group and no myopenia group 44 cases in the non-concurrent group logistic regression analysis was applied to analyze the factors affecting sarcopenia in patients with lung cancer a nomograph model was constructed for predicting sarcopenia in patients with lung cancer the differentiation and consistency of the nomograph model for predicting sarcopenia in patients with lung cancer were evaluated with ROC and calibration curve. Result A total of 96 patients with lung cancer were included in this study and there were 52 patients with sarcopenia the incidence of sarcopenia was 54. 17% 52 / 96 long-term smoking history NRS 2002 score body mass index BMI fat-free body mass FFM muscle mass SLM appendicular skeletal muscle mass ASM body fat BFM were obviously different between the concurrent group and the non-concurrent group P<0. 05 multivariate Logistic regression analysis showed that long-term smoking history NRS2002 score and BMI were the factors affecting sarcopenia in lung cancer patients P<0. 05 the nomograph model shows that the weight of long-term smoking history was increased by 21. 8 points the weight of NRS2002 score was increased by 25 points for every 1 point increase and the weight of BMI was increased by 12. 5 points for every 2 kg / m 2 decrease H-L fit test showed that χ 2 = 3. 891 P = 0. 867 the slope of the calibration curve approached 1 the area under the ROC curve was 0. 917 and the sensitivity and specificity were 92. 31% and 75. 00% respectively. Conclusion Long-term smoking history NRS2002 score and low level BMI are all the factors that influence the occurrence of sarcopenia in lung cancer patients. The nomograph model constructed in this study has high clinical value in the individualized prediction of sarcopenia in lung cancer patients.