Adopting healthy dietary habits, including higher dietary diversity, has been associated with healthy aging. Several scores have been developed to assess the dietary diversity, but none specifically among older adults. Therefore, the present work aimed to develop and validate a healthy dietary diversity score (DAS) in a sample of older adults enrolled in a representative national survey.The studied sample was constituted of 696 older adults aged 60y and over, from the latest cross-sectional French Individual and National Food Consumption study (INCA3). The dietary survey included three 24 hours recalls and a Food Propensity Questionnaire. The occurrence of consumption of 20 food groups weighted by positive (for whose consumptions are healthy and should be encouraged) or negative (for whose consumptions are unhealthy and should be limited) points composed the 20 score components whose sum defined the DAS. The validity of the DAS was assessed by describing its association with the food score components, energy intake, solid energy density (SED), probability of adequate nutrient intake assessed by the PANdiet and with educational and physical activity levels. The DAS ranged from -35 to 115. Higher DAS were positively and significantly associated with more points in healthy score components like Fruits or Vegetables (r= 0.51, p <0.0001 and r= 0.54, p<0.0001 respectively). The DAS was not significantly associated with the total energy intake (r= 0.02, p =0.6). The DAS was significantly positively associated with the PANDiet (r= 0.43, p< 0.0001) while inversely associated with the SED (r= -0.37, p<0.0001). Higher DAS were observed among participants with higher educational and physical activity levels as expected. The DAS we developed is validated to assess the healthy dietary diversity score of French older adults. Beyond, it could be a useful tool to assess the impact of public health nutritional trials.