Objective: To determine whether self-reported discretionary time was associated with physical activity and uptake of a physical activity promotion intervention in a multi-ethnic urban sample. Methods: We examined the association of self-reported discretionary time with hours/week of leisure-time physical activity at baseline and physical activity intervention uptake. Results: Low levels of discretionary time were significantly (P less than 0.01) associated with fewer hours/week (beta = -0.78, 95%CI = -1.34, -0.22) of physical activity at baseline. Discretionary time was not associated with physical activity intervention uptake. Conclusion: Lack of discretionary time may serve as barrier to physical activity, but its importance on intervention uptake is less clear.