ObjectivesInsufficient physical activity (IPA) is a crucial risk factor for non-communicable diseases (NCDs). The elderly population has a higher likelihood of suffering from NCDs. We aimed to estimate the prevalence of and factors associated with IPA among the elderly people in Bangladesh.MethodsWe analysed data from the Bangladesh Food Security and Nutrition Surveillance round 2018–2019, collected from 82 rural, non-slum urban and slum clusters selected using multistage cluster sampling. IPA was defined as <150 min of moderate intensity or <75 min of vigorous intensity or equivalent in a typical week. The weighted prevalence of IPA was estimated by gender and across different variables. Crude and adjusted prevalence ratios were calculated using Poisson regression with robust variance.ResultsThe weighted prevalence of IPA among elderly people was 38.4%, with a slightly higher prevalence in women (39.7% vs 37.3%). Factors associated with higher prevalence of IPA in both sexes were—higher age, living in non-slum urban areas, unemployed or homemaker, not currently married, sedentary behaviour and self-reported hypertension. Further, >10 years of education, inadequate fruits and vegetable consumption, self-reported asthma and higher waist circumference among men; and higher household income and self-reported diabetes among women were associated with a higher prevalence of IPA.ConclusionsIPA is highly prevalent among Bangladeshi elderly men and women. Sedentary behaviour, inadequate fruits and vegetable consumption and higher waist circumference were the modifiable factors of IPA. Evidence from this study can guide the development of appropriate interventions to promote healthy ageing in Bangladesh.