BACKGROUND: The amount of physical activity, sleep, and sedentary behaviour affect several age-related diseases. However, no relevant study about their associations with cardiovascular and musculoskeletal diseases from European older adults is known. METHODS: We investigated the associations of the volumes of physical activity, sleep, and sedentary behaviour with low handgrip strength (HGS), heart attack, hip fracture, rheumatoid arthritis, stroke, and osteoarthritis among European older adults (age ≥ 50 years, n = 819) from ten countries using cross-sectional data from the Survey of Health, Ageing, and Retirement in Europe (SHARE) conducted between 2019 and 2021. We used iso-temporal regression analysis to investigate the associations of lifestyle factors with age-related diseases. RESULTS: The participants who met the weekly recommendation for 150 min of moderate-to-vigorous physical activity (MVPA) had lower prevalence of low HGS, difficulty lifting 5 kg of weight, heart attack, hip fracture, rheumatoid arthritis, stroke, and osteoarthritis. The iso-temporal regression analysis revealed that more light physical activity or MVPA was associated with lower prevalence of difficulty lifting 5 kg of weight and stroke. Lastly, longer sleep or less MVPA was associated with higher prevalence of stroke and difficulty lifting 5 kg of weight. CONCLUSIONS: Collectively, our data shows the associations of several age-related diseases and optimal LPA, MVPA, and an optimal sleep. Our observations may be useful in optimizing lifestyle to combat age-related disorders in European older adults.