Background More and more synchronous multiple primary lung adenocarcinomas (SMPLA) have been diagnosed and surgical treatment has become the mainstay of treatment for them, but there are few reports on the surgical outcome of patients with >= 3 lesions who underwent surgical resection. Therefore, we summarized and analyzed the clinical characteristics and surgical outcomes of these patients, hoping to provide some experience in the diagnosis and treatment. Methods Clinical characteristics and treatment outcomes of patients with >= 3 lesions who have been diagnosed as SMPLA and underwent surgical resection in our hospital from March 2015 to July 2019 were retrospectively reviewed. Results Twenty-eight patients, 20 females and 8 males, with a mean age of 57.7 +/- 5.69 (45-76) years, were finally included. A total of 95 lesions, 86.4% were ground-glass opacity (GGO) lesions (pure-GGO,45.3%; mixed-GGO,41.1%); 51 lesions had EGFR mutations and the mutation rate of invasive adenocarcinoma was significantly higher than that of other pathological subtypes (P < 0.001); the mutation rate of mGGO was also significantly higher than that of pGGO and solid nodule (SN) (P < 0.05). Four and 24 patients respectively underwent bilateral and unilateral surgical resection. The surgical procedure was mainly sublobar resection, and no severe postoperative complications or deaths occurred. After a median follow-up time of 32.2 months, the rates of overall survival and disease-free survival at 3 years were 94.7% and 88.9%, respectively. Conclusions For SMPLA with >= 3 lesions, one-stage resection may be safe and feasible, and surgical procedure was mainly sublobar resection as far as possible, which can yield satisfactory prognosis. EGFR mutation testing should be used routinely in the diagnosis and treatment of patients with SMPLA, especially in the presence of mGGO and invasive adenocarcinoma.