BACKGROUND: Primary malignant tumors of the trachea are extremely rare entities and account for a mere 0.1 percent of all malignancies of the respiratory tract Because of vague localizing signs, symptoms and a usually negative routine chest film, the patients with tracheal tumors are often treated for asthma or chronic obstructive pulmonary disease for considerable period of time before correct diagnosis. METHODS: We Have made a review of the 17 cases of primary tracheal tumors in recent 15 years. We reviewed the clinical features including history of smoking arid respiratory symptoms, the official readings of initial routine chest film, the cytologic examination of sputum, the time of delay in diagnosis, and the response according to the therapeutic modalities. RESULTS: Eight out of 9 patients with squamous cell carcinoma(SCC) were above 50 years old, five out of 6 patients with adenoid cystic carcinoma(ACC) were below 50 years old. The most common location of primary tracheal tumors was the upper one-third of trachea in 8 cases(47%). The most frequent symptoms were dyspnea in 13/17 cases(76%) and then strider or wheezing, cough, and sputum in order. The routine chest roentgenographic examinations wore not helpful to diagnose tracheal carcinoma and the cytologic examinations of sputums were helpful to diagnose tracheal carcinoma in only one case with adenocarcinoma. The mean times of delay in diagnosis of patients with SCC and ACC were S months and 24.9 months respectively. We bad bronchial asthma in 8 cases(47%) and tracheal tumors in 4 cases(23%) as initial clinical impression CONCLUSION: We would like to perform more comprehensive diagnostic too]s(high KVP technique, the fibroptic bronchoscopic examination, chest CT scan etc.) in patients who had the suggestive points for the tracheal tumors(1. unexplained hemoptysis or hoarsness, 2. inspiratory wheezing or stridor, 3. wax arid waning of dyspnea according to changes of position. 4. progressive asthmatics unresponsive to antiasthmatic therapy) and radical resection of tumor or external radiation therapy with curative aim as possible.