The consequences of the strict health restrictions during the first wave of COVID-19 on lung cancer (LC) patients are not known. This cohort study evaluated the impact of the initial lockdown on management of and long-term outcome in LC patients. This exposed-unexposed-type study included two evaluation periods of 6 months each in non-selected patients; one began on the first day of lockdown in 2020, and the other in 2019 during the same calendar period. Various indicators were compared: clinical profiles, management delays and overall survival beyond 2 years. A total of 816 patients from 7 public or private centers were enrolled. The clinical characteristics of the patients in 2020 did not differ from those in 2019, except that the population was older ( = 0.002) with more non-smokers ( = 0.006). Delays for pre-therapeutic medical management were generally reduced after the first imaging in 2020 (1.28 1.1-1.49). In the multivariate analysis, being part of the 2020 cohort was correlated with better prognosis (HR = 0.71 0.5-0.84, < 0.001). The gain observed in 2020 mainly benefited non-smoking patients, along with ECOG PS 0-2 ( = 0.01), stage 4 ( = 0.003), squamous cell carcinoma ( = 0.03) and receiving systemic therapy ( = 0.03). In conclusion, the first lockdown did not exert any deleterious impact on LC patients.