T The Ria rio Reservoir is a reservoir located in Pedongkelan area, Pulogadung, East Jakarta with total area of 26 hectares, located in an urban area with a high population level and high-density development. If solid development in urban areas continues to be carried out without regard to environmental balance, then this can lead to various problems, one of which is the increase in air temperature in urban areas. In urban areas, spesifically urban areas in tropical countries such as Indonesia where air temperatures are generally higher than those outside urban areas and air temperatures could exceed above the maximum temperature of thermal comfort standard. Thermal comfort is the way humans respond to stimuli to the temperature of the surrounding environment. Vegetation has an important role in microclimate amelioration, namely temperature modification, humidity control, solar radiation control and wind speed control. Microclimate is one of the main factors in controlling thermal comfort, therefore it can be said that vegetation plays an important role in controlling the thermal comfort of an area. The main objective of this study is to measure how far the vegetation functions on thermal comfort in the Ria Rio reservoir area. The output of this researchii  will be used as the basis in the landscape design development, especially in the use of vegetation that will be applied in the development of the region. This study uses descriptive qualitative methods and quantitative methods. Qualitative methods are carried out by evaluating thermal comfort using EnviMet simulation program and direct measurement, the result will be adjusted to the thermal comfort standard. Vegetation criteria will be assessed as it’s function in temperature modification, humidity control, wind control and solar radiation. The results of the assessment will be assessed quantitatively to see how much vegetation functions in thermal comfort.