Introduction. In response to the COVID-19 pandemic many countries have implemented periods of national lockdown that have substantially changed the daily life of people worldwide. In France, a national quarantine requiring people to stay at home and the closure of all but essential public places were implemented for the rst time on March 17, 2020 for 8 weeks. Using questionnaires and interviews, recent studies reported relationships between life disruptions associated with COVID-19 quarantine [1], and alterations in dietary patterns [2] and inversely, maintenance of dietary patterns [1,3] and lifestyle habits. Thus, the aim was to determine (using food diary analysis at several time points) the impact of the COVID-19 lockdown on the dietary patterns in active and non-active French adults. Methods. A total of 220 participants, age > 18 years, who had never been positive for COVID-19 took part in an online survey including sociodemographic, eating behavior, weight change, sedentary behavior (SED) and physical activity (PA) questions at different times during (3rd week of lockdown: P1; and 7th and 8th week of lockdown: P2) and post lockdown (1-month post: P3). Participants completed food diaries every 4 days over these periods. Participants who did not complete at least 1 food diary in each period were excluded from the nal analysis. Energy Intake (EI), nutrient breakdown and fluids consumed in P1, P2, and P3 were obtained from the food diary analyses. Linear mixed eects models were tted to analyze the differences in dependent variables between the three lockdown time periods. Results. Thirty-ve females and 15 males (age, 4515 yrs; BMI, 22.63kg/m2; 94% with an outdoor space) completed questionnaires and food diaries. Sixty percent had a professional activity during the lockdown, 80% of them working as executives, employees, and retired, and 58% had at least a master's degree. 54% declared themselves to be active (comply with the PA recommendations [4]) and 72% to be non-sedentary (> 7h/d SED) at the time they entered the lockdown. EI (kcal/d) and nutrient consumption did not dier between active (1661.9 458.1) and non-active (1789.1 606.4), or sedentary (1714.6 523.1) and non-sedentary individuals (1742.6 539.0) nor between lockdown time points. Alcohol consumption and EI were consistently higher in males than in females but did not dier between periods. Sedentary participants consumed signicantly (p=0.02) more alcohol than non-sedentary participants in P1, P2 and P3. More than 60% of participants reported no change in the number of meals and snacks between periods. Almost half of the participants reported a variation of body weight in P2 vs P1 (44% loss and 56% gain, median change: 1.0 kg) and 40% reported a variation of weight in P3 vs P2 (55% loss and 45% gain, median change: 0.0 kg). Conclusion. For the rst time, using a food diary analyses revealed that the lockdown period had minimal impact on the dietary intake and eating behaviors in active and non- active French adults. Apart from methodological considerations, the maintenance of dietary patterns could be partly explained by the environmental conditions of the population studied.