Physical activity is an effective way to promote the health of older adults. However, several individual factors may affect motivation to engage in physical activity. The purpose of this study was to investigate which motivational factors are associated with high levels of physical activity among older people. The study is part of a larger FINGER study, which includes 1260 people with a mean age of 69 years. Physical activity and motivational factors were assessed using questionnaires and the associations were analyzed with multivariate logistic regression models. The results showed that persons who perceived physical activity as fun, who wanted to maintain physical and mental health, and who met other people when engaging in physical activity were more physically active. The results indicate that it is important to provide information about the benefits of physical activity, to support engaging activities that are perceived joyful, and to provide possibilities to be socially active.