Study’s purpose: to assess effect of covid 19 pandemic on physical activity, dietary behaviours and sleep quality among elderly. Methodology: A comparative descriptive study conducted in a rural area at Sharkia Governorate, Manshet Abd Elatif Waked with a random sample composed of 300 older adults Physical Activity was measured by International Physical Activity Questionnaire - Short Form, Dietary Behaviours were measured by Short Diet Behaviours Questionnaire and Sleep Quality was measured by Pittsburgh Sleep Quality Index (PSQI). Major results: the total mean score of physical activity among the studied elderly was 7.62±3.50before covid 19 then decreased to be 4.75±4.16 during covid 19, total mean score of diet behavior was6.64 ± 1.52 before covid 19 then decreased to 6.35 ± 1.50 during covid 19, and the total mean score of sleep behaviors among the studied elderly was 4.88±2.24 before covid 19 then increased to be 5.51±2.41 during covid 19,that indicates poor sleep quality during covid19. Statistically significant negative correlation between physical activity mean score and sleep behaviors and. Statistically significant positive correlation between diet behaviors mean score and physical activity mean score Recommendations: development of health promotion interventions to support positive physical activity, dietary behaviors, and sleep quality using alternative coping strategies.