Purpose: The purpose of this retrospective study was to evaluate common clinicopathological factors and clarify the prognostic factors of small-sized peripheral-lung squamous cell carcinomas.Methods: We retrospectively reviewed 71 patients with peripheral squamous cell carcinoma ≤3 cm in diameter, who were surgically treated between January 1989 and December 2010. Patients undergoing partial lung resection without lymph node dissection were excluded. The median follow-up for living patients was 63 months.Results: The overall 3- and 5-year survival rates were 83.9% and 74.7%, respectively.Although the ROC curve of serum carcinoembryonic antigen (CEA) levels showed marginally significance (P = 0.050), multivariate analyses revealed that age (P = 0.043), lymph node metastasis (P = 0.004), and preoperative serum carcinoembryonic antigen (CEA) level (P = 0.037) were independent prognostic factors. For pathologic N0 patients, there was a significant difference for recurrence-free survival based on CEA levels: patients with normal CEA levels (n = 40), 5-year-recurrence-free rate = 93.5%;elevated CEA (n = 14), 5-year-recurrence-free rate = 72.7% (P = 0.0160). The distribution of tumor cells immunoreactive for CEA was significantly associated with serum CEA levels (P = 0.033).Conclusion: Age, lymph node metastasis, and serum CEA level are independent prognostic factors for small-sized peripheral-lung squamous cell carcinoma.