Objective To determine the most appropriate T-stage and surgical resection range of non-small cell lung cancer(NSCLC) with adjacent lobe invasion (ALI). Methods Fifty one NSCLC patients who were confirmed as direct ALI were divided into an ALI-T2 and an ALI-T3 group according to the eighth edition of TNM classification. Cases were matched by propensity score matching method at a ratio of 2∶1. The overall survival (OS), progression free survival (PFS), postoperative hospitalization, and postoperative complications among the groups were compared. Results Patients' characteristics were comparable among the groups. Three-year or 5-year survival rate in the ALI-T2 group, the single-lobe invasion T2 (SLI-T2) group, and the T3 (SLI-T3) group was 73.90% and 61.60%, 89.60% and 89.60%, 68.90% and 61.20%, respectively. The OS of SLI-T2 group was significantly higher than that of the ALI-T2 ( P=0.042) group and with similar survival in the SLI-T3 group( P=0.955). In the survival analysis of the ALI-T3 group, the 3-year or 5-year OS of the SLI-T3 group was 70.80% and 65.70%, respectively, while in the poorest prognosis ALI-T3 group was only 31.60% and 21.00% ( P=0.009), respectively. However, no statistical difference was detected between the ALI-T3 and SLI-T4 groups ( P=0.343). The PFS of the patients in the ALI-T3 group was closer to the SLI-T4 group level while lower than that of the SLI-T3 group, but the trend had not been confirmed by statistical analysis ( P 1=0.071, P 2=0.648). The OS and PFS did not differ between the patients undergoing a lobectomy plus wedge resection (LWR) and those undergoing a bilobectomy or pneumonectomy. Compared with a bilobectomy or pneumonectomy, LWR had distinct advantages in the postoperative hospital stay (6.90±3.11days vs. 9.23± 4.43 days, P=0.030), the postoperative duration of drainage (4.41±2.98 days vs. 6.50±4.11 days, P=0.041) and complication rates (4.00% vs. 31.58%, P=0.032). Conclusions We believe that T1-2 stage tumor invading adjacent lobe should be classified as T3 and ALI-T3 tumor should be revised as T4. Beside that, LWR could be considered as a reasonable surgical option for patients with lesser invasive depth (less than 2 cm) in the adjacent lobes.