Objectives: The currently implemented healthcare reform in China requires substantial capital investment. Although overtreatment results in serious waste, inappropriate laboratory use is widespread, and overuse of tumor markers (TMs) has attracted increasing attention. Design: Retrospective study. Setting: The respiratory, thoracic surgery, and oncology departments of three hospitals in Shanghai, from 2014 to 2015. Participants: Patients with chronic obstructive pulmonary disease (COPD) and primary bronchogenic lung cancer (PLC). Based on clinical guidelines and physician experience, the criteria of suitability of TM examinations were determined, and the number, cost, and proportion of inappropriate TM requests were analyzed. Results: The area under the receiver operating characteristic (ROC) curve for CEA+CYFRA211+SCC+NSE in COPD and PLC patients was 0.813, in accordance with the cost-effectiveness principle, indicating good clinical and health economics values. In the 2706 patients, 12,496–16,956 (58.27–79.06%) of TM requests were inappropriate. Furthermore, the involved expense was 650,200–1,014,156 yuan, accounting for 7.69–12.00% of examination expenses, and 1.35–2.11% of hospitalization costs. Conclusions: We found that the inappropriate use of TMs was widespread for patients with pulmonary disease. Clinicians should use TMs strictly according to the guidelines to effectively manage laboratory resources and control costs.