This study determined the levels of serum ferritin (SF) and carcinoembryonic antigen (CEA) in elderly patients with advanced primary lung cancer (PLC), and aimed to investigate the correlation between the SF level and clinical characteristics and compare the positive rates of SF and CEA levels in PLC patients and those in normal subjects. The SF and CEA levels of 69 elderly cases of advanced PLC and 63 elderly controls were determined by electrochemiluminescence method. The correlation between each independent clinicopathological characteristic and levels of SF and CEA was calculated. The positive rates of SF and CEA levels in PLC patients and those in normal subjects were compared. The results revealed that the level of SF in controls was significantly lower than those in patients with advanced LC (145.04 ± 141.77 vs. 293.57 ± 274.95 ng/ml, t = -3.845, P = 0.000). There was a statistically significant difference between SF level and gender, smoking, and regional lymph node metastasis, respectively (P < 0.05). The positive rate of SF combining with CEA was significantly higher than those of SF and CEA alone in patients with advanced PLC. High serum level of SF is helpful for diagnosing PLC in elderly patients and indicates poor prognosis.