Abstract: Species response to climate change can be viewed in three main directions: range changes, phenological changes, and genetic selection of different traits to ensure adaptation to new conditions. Climate-niche factor analysis (CNFA) is a tool developed in order to assess species vulnerability to climate change. In order to test the usefulness of CNFA method, we have chosen the long-legged buzzard (Buteo rufinus) as a case study. This species breeds in south-east Europe, from the southern Balkans to north-western Mongolia and China, preferring open areas, arid steppes and semi-desert or mountains. According to CNFA model, long-legged-buzzard habitat receives less precipitation during the warmest period (PWQ), relative to European area, and exhibits less temperature variations during the year (TS). On the other hand, the presence of the long-legged-buzzard is associated with high values for mean diurnal range (MDR) and precipitation variations (PS). The greatest sensitivity of this species came from amount of precipitation during the warmest period (PWQ) and temperature and precipitation variations during the seasons (TS and PS). Long-legged-buzzard shows the most vulnerability in relation to precipitation of warmest period (PWQ), temperature seasonality (TS) and annual mean temperature (AMT).