Objective To explore the correlation between preoperative pulmonary function indices and frailty in elderly male patients. Methods A total of 127 male patients, aged≥65 years, who underwent pulmonary function examination and accepted preoperative interviews in pre‑anesthesia consultation clinics of North Jiangsu People's Hospital from February 2021 to March 2021 were enrolled. According to the Fried Frailty Phenotype Criteria, they were divided into three groups: a non‑frailty group (n=57), a pre‑frailty group (n=56), and a frailty group (n=14). Their grip strength, smoking history, combined basic respiratory diseases were compared. Furthermore, their pulmonary function indices were compared, such as vital capacity (VC), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), FEV1/FVC and the maximal voluntary ventilation (MVV). The correlation between pulmonary function indices and frailty was evaluated by logistic multivariate regression analysis. Results Compared with the non‑frailty group and the pre‑frailty group, patients in the frailty group were older (P<0.05), with significantly decreased grip strength (P<0.05). The frailty group also presented increased incidences of weight loss, low physical activity, fatigue, slow gait and decreased grip, compared with the non‑frailty group and the pre‑frailty group (P<0.05). Compared with the non‑frailty group and the pre‑frailty group, patients in the frailty group showed remarkable decreases in pre⁃operative VC, FEV1, FVC and MVV, and increases in FEV1/FVC (P<0.05). Compared with non‑frailty group, VC, FVC and MVV decreased in the pre‑frailty group (P<0.05), while FEV1/FVC increased in the pre‑frailty group (P<0.05). There was no statistical difference in FEV1 between the two groups (P>0.05). No statistical difference was found in other indices among the three groups (P>0.05). Age [odds ratio (OR) 1.197 (95%CI 1.007,1.423), P<0.05] and MVV [OR 0.858 (95%CI 0.738,0.996), P<0.05] were independently associated with frailty. Conclusions The preoperative VC, FEV1, FVC and MVV of elderly male patients with frailty were lower than those of healthy and pre‑frail ones. Higher age and lower MVV are independently correlated with frailty.