Paper represents the analysis of the change in the outdoor comfort during the summer days of open public space of the main square in Leskovac. The analysis covers the present state, two rewarded design proposals at urban design competition and proposal resulting from the evaluation of these solutions. The article focuses on the thermal comfort in outdoor space as a one of indicators in competitions of urban design, considering the fact that the re-design of public spaces often has a negative consequences of decisions made during the competitions. Following the thesis that successful public spaces should be responsive to the needs of their users, the paper considers the thermal comfort as the main quality of open public space. Analysis of microclimate could help designers to create comfortable urban place, which could attract vast number of users throughout the year, especially during hot summer periods. The aim of this paper is to highlight the complexity of the relationship between microclimate comfort in public open spaces and urban design, especially interventions such as implementation of the greenery and new surface materialization in order to emphasize the importance that this relationship has to be taken into account in urban design competitions. (C) 2015 Elsevier B.V. All rights reserved.