The Specific objectives of this study are to asses impact of land use and climate change on TikurrnWuha River located at Awassa Lake catchment. Hydrologic model, HEC-HMS model was usedrnto assesâ€™ impact of climate and land use change.rnOrthorectified Landsat MSS, TM and ETM+ images covering the study area was classified byrnsupervised image classification using maximum likelihood classifier (MLC). The sample set forrnthe classification was created using the combination of bands 7, 4, 2 (for Landsat TM and ETM+rnimages of year 1986 and 2000, 2005,) and bands 4, 2,1 (for Landsat MSS image of year 1973).rnResult of image classification showed 28.77% reduction in forest cover, 3.6% reduction in lakerncover, 23.49% increase in agricultural land, 3.6% increase in swamp and 5.3% increase inrngrassland within the span of 32 years from 1973 to 2005. Hydrologic impact assessmentrnindicated that with the land-cover changes that have occurred, there is a change on the catchmentrnrunoff. This study reveals that watersheds run off was lower by 5.79 % in period 1973, 0.27% inrn1986 compared to period of 2005 as reference.rnStatistical Down-Scaling Model (SDSM) was used to derive local scale information from globalrnclimate scenarios generated by GCMs. Among four scenario families of Special Report onrnEmissions Scenarios (SRES), three of them (A1B, A2 and B1,) scenarios were used in this study.rnHistorical weather data collected were used to calibrate and validate downscaling models. Afterrncalibration and validation, the downscaling model was used for computing future temperaturernand precipitation pattern. SDSM downscaled future precipitation was used in hydrologic modelrnto asses impact of future climate change. The assessment showed that average mean flowrnincreased in the future periods considered (2015 - 2035, 2040 - 2050 and 2080-2099). SDSMrndownscaling data resulted increase in the mean annual flow by minimum of 20.05 % andrnmaximum of 51.67 % during time periods considered for three of emission scenarios considered.rnImpact assessment of land use change showed that the runoff volume of Tikur Wuha Riverrnincreases over past 32 years. Climate change impact analysis also showed that the river flowrnwould increase in future.