To evaluate the clinical usefulness of surgical resection of persistent malignant-looking ground-glass-opacity nodules (GGN) without a preoperative tissue diagnosis.From September 1998 to November 2011, we retrospectively enrolled 288 patients (126 men, 162 women; mean age, 59.3 years) with lung adenocarcinoma proven by surgery and which appeared as GGN on chest computed tomography (CT, ground-glass-opacity [GGO] proportion >20%). We divided the study subjects into 2 groups: patients with a preoperative tissue diagnosis (PTD group, n = 207) and patients without a preoperative tissue diagnosis (No-PTD group, n = 81). In patients with GGN having GGO ≥ 90% (n = 140), we divided them into 2 groups: PTD group (n = 83) and No-PTD group (n = 57). The clinical and surgical outcomes were compared between the 2 groups.In 204 patients who underwent lobectomy for stage Ia lung cancer, there was no significantly different recurrence-free survival between the 2 groups (P = 0.721). A significantly lower percentage of No-PTD group waited >14 days for surgery (77.8% vs 87.9%, P = 0.030) and were hospitalized for >7 days (56.8% vs 89.9%, P < 0.001). They showed a shorter mean surgery time (136.9 vs 155.0 minutes, P = 0.019). In patients with GGN having GGO ≥ 90%, the results were the same as those of all of the study subjects.No-PTD group can gain benefits perioperatively, showing no different recurrence-free survival with PTD group in stage Ia lung cancer.