These days, the research studies on climate variability and change are hot topics in a global climatic research. The warming trend has been characterized by a decrease in Diurnal Temperature Range (DTR) as result of an increase in minimum temperatures experienced during night time. Many factors have been identified as possible reasons for this decrease in DTR like the cloud cover, increase greenhouse gases, increased urbanization, change in land usage, aerosols etc. This study aims to find out observed trends in the maximum and minimum temperature over Addis Ababa City. Meteorological data used in this study was obtained from National Meteorological Agency of Ethiopia for the period 1951-2017. The long-term change in temperature has been assessed by linear trend analysis. In this study, an increasing trend in mean of maximum and minimum temperature was found to be more evident and statistically significant based on Mann-Kendall trend test. In particular, in Addis Ababa City, April and annual maximum temperature has shown significant increment by 0.36 C and 0.245 C per decade, respectively.