Purpose This retrospective study aimed to investigate changes in pulmonary function among patients undergoing computed tomography (CT)-guided microwave ablation (MWA) for the treatment of pulmonary ground-glass nodules following lobectomy. Materials and methods Fifty-two patients with pulmonary ground-glass nodules (GGN) who underwent lobectomy and were subsequently diagnosed with non-small cell lung cancer (NSCLC) were included in the study. Pulmonary function tests (PFTs) were conducted at baseline and again 1 month after microwave ablation (MWA). The assessed parameters included vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1 percentage (FEV1%), peak expiratory flow (PEF), maximal voluntary ventilation (MVV), and maximum mid-expiratory flow (MMEF). The measurements obtained 1-month post-MWA were compared to the baseline values. Results The mean values for VC, FVC, FEV1, FEV1%, MMEF, PEF, and MVV at baseline and 1-month post-MWA for all patients were as follows: VC (3.01 ± 0.68vs. 2.88 ± 0.67, P = 0.348), FVC (3.07 ± 0.75 vs. 2.95 ± 0.69, P = 0.430), FEV1 (2.29 ± 0.61 vs. 2.14 ± 0.55, P = 0.228), FEV1% (74.26 ± 7.70 vs. 72.41 ± 9.40, P = 0.316), MMEF (1.88 ± 0.81 vs. 1.74 ± 0.72, P = 0.410), PEF (5.03 ± 1.62 vs. 4.54 ± 1.53, P = 0.179), and MVV (77.69 ± 22.21 vs. 73.15 ± 17.63, P = 0.286). For the eight patients who underwent ablation of two or more lesions simultaneously, the mean values for VC, FVC, FEV1, FEV1%, MMEF, PEF, and MVV at baseline and 1 month post-MWA were as follows: VC (2.67 ± 0.90vs. 3.05 ± 0.97, P = 0.341), FVC (2.82 ± 0.94vs. 3.10 ± 0.92, P = 0.430), FEV1 (1.97 ± 0.69vs. 2.07 ± 0.69, P = 0.709), FEV1% (70.01 ± 7.24 vs. 66.27 ± 4.47, P = 0.082), MMEF (1.28 ± 0.80 vs. 1.35 ± 0.58, P = 0.777), PEF (4.43 ± 1.44 vs. 3.87 ± 1.40, P = 0.074), and MVV (65.22 ± 16.50 vs. 72.26 ± 12.28, P = 0.222). No significant differences were observed in the PFT results before and 1 month after MWA. Conclusions MWA is a localized treatment that spares lung parenchyma. The pulmonary function 1 month after MWA did not statistically differ from baseline levels, suggesting that MWA may not adversely affect pulmonary function.