Little is known about the longitudinal predictors of the need for care in old age. However, the knowledge of these factors is important for developing strategies for prevention or delay the need for care. Thus, we aimed at investigating the factors affecting the need for care in old age. In this population-based prospective cohort study (AgeCoDe, with n=3 217 individuals aged 75 years and above at baseline), the need for care was observed over 4.5 years. The need for care was quantified by the care level defined by the German Law (§ 15 SGB XI). Longitudinal predictors (sociodemographic variables, impairment in mobility/hearing/vision, dementia and depression) of the need for care were examined by using Random Effects Logit regressions. Longitudinal regression analysis revealed that the probability of the need for care significantly increased with the occurrence of dementia (OR: 48.2), mobility impairments (aggravated walking, OR: 26.4; disability of walking, OR: 747.9) and age (e. g. 90 years and above vs.<80 years, OR: 32.3). The influence of family status, living conditions, visual impairment and depression on need for care was markedly smaller, and the effect of hearing impairments did not achieve statistical significance. In order to prevent or delay the need for care in old age, treatments should aim at preserving mobility and cognition. Due to demographic ageing, developing such programs is of major importance for health policy.