Water problems arising from the negative effects of climate change will cause serious challenges to cities in the near future. Sudden, heavy rainfall in a short time as well as the summer drought periods can be a major concern for urban water management systems. In addition to overloading the urban sewer system, urban flash floods caused by large amounts of precipitation can lead to serious damage in connection with surface runoff; furthermore, this significant amount of water is removed from the water cycle of the city without utilization (infiltration, storage). Various water management and hydrology models, such as UFORE-Hydro used in our analyses, can serve as suitable tools for investigating these processes. In our research, we examined the role of vegetation covered areas in urban water cycle, paying special attention to their impact on surface runoff. The results of modeling in Szeged sample areas show that vegetation can considerably reduce the volume and amplitude of surface runoff. In the scenario studies, vegetation has always changed the rate of runoff in a favorable direction, thus our findings support the necessity of green infrastructure developments.