Objectives: Defining the clinical characteristics and treatment of 1158 lung cancer patients at Cho Ray Cancer Center. Methods: A cross-sectional retrospective study of 1158 lung cancer patients treated at Cho Ray Cancer Center from 01.01.2009 to 31.12.2011. Results: Of the 1158 patients, there were 821 men (70.9 percent) and 337 women (29.1 percent). The ratio male / female was 4/1. The median age was 56, mostly in age group of 50-59. The most common pathological type was adenocarcinoma (64.3 percent). The TNM staging in the order of I, II, III, IV stages were 2.2 percent, 8.7 percent, 38.8 percent, 50.3 percent in respectively. Common sites of metastases were brain (40 percent) and liver (21.8 percent). For treatment, the proportion of multimodality treatment was 33.2 percent, palliative care treatment only occupied 4.6 percent. The proportion of patients treated with curative aim was 29.6 percent. Conclusions: Most patients with lung cancer were diagnosed in advanced stages in Cho Ray hospital. However, the proportion of patients treated by combining multimodality was encouraging.