Jedeb River is one of the major tributary of Blue Nile River. However, the stream flow trend ofrnJedeb River has been decreased specially in dry seasons. Climate variability and human activityrnhad been identified as the two main reasons for the decrease in stream flow. Here, climaternvariability refers to variability in precipitation and temperature and human activity is the activitiesrnwhich includes direct withdrawal of water (for irrigation, domestic and non-domestic use) andrnland use land cover change. Understanding the individual contributions of climate variability andrnhuman activities to changes in runoff is important for sustainable management of regional waterrnresources. To detect the cause of stream flow change, the temporal trends of seasonal stream andrnannual flow (Dry, less rainy, rainy and annual) during 1980â€“2014 were first explored by modifiedrnMann-Kendall trend. Annual, less rainy and rainy seasonâ€™s display slightly decreasing trend butrnnot significant, but in dry season significant decreasing trend occur in Jedeb River. Change pointsrnfrom 1980 to 2014 are detected by pittitt test. From the result, the year 1998 is identified as abruptrnchange year. So that, the stream flow data set is divide into two periods as the pre-change periodrnand post-change period.rnThree methods including climate elasticity, hydrological sensitivity and hydrological modelrnmethod was used to detect and quantify the hydrological runoff response to climate variability andrnhuman activities, based on the assumption that climate variability and human activities are thernonly drivers for stream flow. We found that human activities has 75.8% ,73% and 77.4%rncontribution for stream flow change by using climate elasticity, hydrological sensitivity andrnhydrological model method respectively. Whereas climate variability has 24.2%, 27% and 22.6%rncontribution for decreasing stream flow by using climate elasticity, hydrological sensitivity andrnhydrological model respectively. From all method human activity was detected as the dominantrnfactor for decreasing stream flow. The study provides scientific foundation to the stakeholder tornunderstand the causes of water resources redaction and useful information for the planning,rnmanagement and development of water resources.