Objective. Considering the poor effect of routine nursing program on patients with lung cancer after chemotherapy, a retrospective cohort study was conducted to elucidate the effects of respiratory training based on ADOPT mode combined with continuous nursing on quality of life, mental health, and self-efficacy in patients undergoing lung cancer chemotherapy. Methods. Sixty patients with lung cancer admitted in our hospital from January 2019 to April 2021 were selected. Patients in both groups received ADOPT breathing training. Patients who underwent routine nursing were assigned into control group ( n = 30 ) and patients with continuous nursing were set as study group ( n = 30 ). The differences in nursing satisfaction, self-management efficacy, quality of life score, mental health, family care index, and self-transcendence scale scores of patients with lung cancer were determined. Results. First of all, we compared the baseline data of the two groups, and there was no statistical difference. In the comparison of nursing satisfaction between the two groups, 24 cases in the study group were very satisfied, 5 cases were satisfied, 1 case was general, and the satisfaction rate was 100%, whereas in the control, 14 cases were very satisfied, 8 cases were satisfied, 4 cases were not satisfied, and the satisfaction rate was 86.67%. Compared to the control, the nursing satisfaction was higher in the study group ( P < 0.05 ). There exhibited no significant difference in the sense of self-management efficacy between the two on the day of admission ( P > 0.05 ). After nursing, the scores of self-management efficacy were higher in the study group, compared to the control ( P < 0.05 ). In contrast to control, the scores of self-management efficacy at discharge and 1, 3, and 6 months after discharge were higher in the study group ( P < 0.05 ). In terms of the scores of quality of life of patients with lung cancer, on the day of admission, no significant difference exited ( P > 0.05 ). The scores of quality of life at discharge and 1, 3, and 6 months after discharge of the study group were higher compared to the control ( P < 0.05 ). In the comparison of mental health, there was no significant difference between the two groups on the day of admission ( P > 0.05 ), but the scores of anxiety and depression in the two groups decreased after nursing, and the scores of anxiety and depression in the study group at discharge and 1 month, 3 months, and 6 months after discharge were lower than those in the control group ( P < 0.05 ). In terms of the family care index, there was no significant difference between the two groups at admission ( P > 0.05 ), but after nursing, the family care index of the two groups increased, and the family care index at discharge and 1, 3, and 6 months after discharge was greater in the study group ( P < 0.05 ). In terms of the score of self-transcendence scale, there exhibited no significant difference on the day of admission ( P > 0.05 ), but the score of self-transcendence scale of the two groups increased after nursing. Furthermore, compared to the control, the score of self-transcendence scale at discharge and 1 month, 3 months, and 6 months after discharge in the study group was higher ( P < 0.05 ). Conclusion. Patients undergoing lung cancer chemotherapy using ADOPT-based breathing training combined with continuous nursing can effectively facilitate the overall quality of life of lung cancer chemotherapy patients, promote the mental health and self-efficacy of patients with lung cancer chemotherapy, and then reduce the medical burden of patients. The nursing model based on ADOPT breathing training combined with continuous nursing is worthy to be applied in the rehabilitation of patients with lung cancer.