This paper aims to consider Three matters (1) how urban structure effects on the climate change (2) how climate change like as heat island have an influence to the vulnerable low income household and the elderly in terms of lifestyle and economic life in urban area (3) the execution of afforestation campaign by local government and its economic and cultural social implication to the urban. Firstly, urban heat island phenomenon is deeply influenced by the urban structure which includes physical characteristics of urban structure and industry and the natural characteristics of the city like as the green axis of and ratio of green field of inner city. The cost for maintaining amenity in household has increased continuously and effects on the preference of residential type. Secondly, Cities of Korea like as the process of urbanization in developing countries have concentrated on its expansion of artificial urban structure. Therefore cities have got an inadequate environment to scope with natural changes like as climate changes and heat island phenomenon in urban area. These phenomena gave significant effect on residential environment in vulnerable urban area like as the change of lifestyle and increasement of individual expenditure to control the temperature of household and to maintain its amenity. Thirdly, local government adopted afforestation campaign as a countermeasure for heat island mitigation in urban area like as ‘Planting ten million trees’, wall surface afforestation, and making park in the center of the city. After adopting this policy, the temperature of Daegu was decreased by 1.2°C on the average compared with highs of average year. Even though the effectiveness of its policy, the social, cultural, economic implication of adapting the method of afforestation campaign should be described. This paper explore the relationship the environment with urban structure and human life in a macro view through the understanding that climate can be influenced by the urban structure and also climate change gives direct impact to human in cultural, social, economic aspects.