Background: There is few published data’s of the management of patients with a HNC and a synchronic lung cancer. The aim of this observational study was to describe in a multicentric setting the management of these patients. Methods: The study included, consecutively all patients diagnosed between January 2011 and December 2015 in 19 French centers with a HNC and a synchronic lung cancer. Patients were described per the clinical characteristics, management and outcomes. Patient characteristics and treatment information was analyzed descriptively. Kaplan-Meier estimation was used to assess median overall survival. Results: The study included 62 patients: men : 84%; 62 ± 1.3 years old, current smokers: 68%, asbestos exposure: 11%; performans status: 0 and 1 for 22.5% and 66% of the patients respectively; hight rate of comorbidities, cardiovascular: 68%, COPD: 32%. Main histology for HNC was squamous: 98%, in oral cavity: 32%, oropharyngeal: 21%, hypo-pharyngeal: 22.5% and laryngeal: 24%. T classification was T1, T2, T3 and T4 in 18%, 29%, 29% and 16% of cases respectively, and N classification was N0, N1, N2, N3, for 40%, 24%, 21% and 6% of cases respectively. The main treatment was surgery, 47%, and chemo-radiotherapy, 52%. The diagnosis of lung cancer impacts the HNC management in 21% of the cases. Median delay between HNC and first day treatment was 54 ± 6 days. HNC progressive free survival rate was 68% at 2 years. Lung cancers were localized (stages I: 81%, stages II: 19%), squamous: 32%, adeno-carcinomas: 47%, larges cells or sarcomatosis: 7%. Main treatments were surgery: 56%, mainly lobectomy, radiotherapy: 15%, radio-chemotherapy: 10% and chemotherapy alone: 26%. Six patients didn’t receive active treatment. Median delay of treatment was 150 ± 16 days. Lung cancer progressive free survival rate was 28% at 2 years. OS was 55% at 2 years, better for stage I than stage II lung cancers. Conclusions: Synchronic lung cancer at HCN diagnosis impact management and outcomes of HNC with a delay in the management of lung cancer. Specific recommendations should be elaborate to improve the management of these patients.