Background There are limited studies on treatment and survival analysis among patients with unresectable Stage IIIB or IV non-small cell lung cancer (NSCLC) in routine practice in China. To address this gap, we conducted a prospective observational study in a cohort of patients treated at 11 hospitals in China. Methods This was a multicentre, prospective cohort study including patients with newly diagnosed unresectable Stage IIIB or IV NSCLC from June 26th, 2015 to April 28th, 2017. Patient baseline characteristics, disease characteristics, and anti-cancer treatments were obtained by medical chart review. The overall survival (OS) from the initiation of first-line treatment was analysed by the Kaplan-Meier method. Factors associated with survival were analysed by univariate and multivariate Cox regression models. Findings Among 1324 patients enrolled with median follow-up duration of 15.0 (range: 0.0-42.1) months, 83.5% (1105/1324) of them received first-line chemotherapy of which platinum-based compounds were the dominated agents. Overall, 30.9% (409/1324) of patients received targeted therapy as 1st-line treatment including 65.0% (266/409) EGFR-TKIs and 5.1% (21/409) ALK-TKIs. Of all eligible patients, gene testing rates were 44.0% (583/1324) for EGFR mutations, 17.0% (225/1324) for EML4-ALK gene fusions, and 8.3% (110/1324) for ROS1 gene fusions. The EGFR-TKIs were administered to 63.9% (179/280) of EGFR mutated patients as first-line treatment. The overall median OS was 23.2 (95%CI 19.5-25.5) months, and patients treated at tier 1 cities had better OS than that of tier 2 cities. Also, the OS in patients with EGFR mutation was longer than those with EGFR wild type. Multivariate Cox regression models suggested that male, education below high school, tier 2 cities, smoking history, and multiple metastases were associated with poor survival. Interpretation The gene test coverage was relatively low among the studied population, and over half of EGFR mutated patients received EGFR-TKIs, suggesting that the result of genetic tests in real-world settings may not always indicate the selection of treatment. The OS benefit observed from patients treated in tier 1 cities and those with EGFR mutation may indicate a need for broader gene test coverage, providing NSCLC patients with personalized treatment according to the results of genetic tests. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)