Heat problems in the tropical countries cause thermal discomfort affecting human activity. Tree-shaded areas can reduce the heat effect by amelioration of microclimate and enhances the human thermal comfort outdoors. The objective of this study is to investigate thermal comfort and activity in tree-shaded areas in the green space of the tropical Yogyakarta, Indonesia. The investigation of thermal comfort in tree-shaded areas was conducted by structured interview, microclimate measurement and activity observation. The shade coverage was analyzed by hemispherical images and Sky View Factors (SVF) with classification of soft and hard surfaces. It was described that the cooling effect of tree-shaded areas is significant on thermal comfort in the tropics. The thermal sensation of cool-slightly cool-neutral was a condition of high comfort in tree-shaded areas in the tropics. The shade coverage was indicated by SVF values as full shade (0.0-0.2), not-full shade (0.2-0.4), and no shade (0.4-0.5). Tree-shaded areas with no shade and hard surface (NS-H) were not recommended in tropics because of the lack of comfort. The long duration of spending time, the high intensity of activity, and the willingness of using shade areas can be the indications of comfort in tree-shaded areas.