Attitudinal and psychosocial outcomes of a fitness and health education program for adults with Down syndrome were examined. Participants were 53 adults with Down syndrome ages 30 years and older (29 females, 24 males, M age = 39.72 years) who were randomized into a training (n = 32) or control group (n = 21). The training group participated in a 12-week, 3 days per week, exercise and health education program. Outcome measures included attitudes towards exercise (cognitive–emotional barriers, outcomes expectations, and performance self-efficacy) and psychosocial well-being (community integration, depression, and life satisfaction). Compared to controls, the training group showed significant changes in attitudes towards exercise, including increased exercise self-efficacy, more positive expected outcomes, fewer cognitive–emotional barriers, improved life satisfaction, and marginally lower depression.