Even if almost 70% of the water used worldwide is applied for crop irrigation, to meet global food demand, irrigation systems structural design, management, and maintenance have been inadequate. Therefore, the study assesses the efficiency of Wurko small-scale irrigation scheme in Lake Tana Sub-Basin, Blue Nile Basin, Ethiopia. Of the 85 ha designed command area, 61 ha was active during the study season. In this finding, a single irrigation season (December to June) of the year 2024 has been taken into consideration, based on 22 years of metrological data (2000–2021). Field observations, discharge measurements in the canals, measurements of water applied to the field, household survey and examination of moisture contents of the soil before and after irrigation, determination of soil physical properties were the primary data whereas climatic data, agronomic data, yields, command and cropped areas, and report of other documents are used as secondary data. The data are analyzed using the CROPWAT 8.0. The findings of the internal performance indicators were 77.51%, 70%, and 53.56% for conveyance, application, and overall efficiencies, respectively. The results of the external performance indicators, relative water supply, relative irrigation supply, water delivery capacity, irrigation ratio, and the sustainability of an irrigated, output per cropped and command area ,output per irrigation supply and water consumed were, in that order, 1.55, 1.62, 1.24, 0.72,0.9, 14637 US$/ha, 10504 US$/ha, 14.15 US$/m3, and 2.69 US$/ m3, respectively. According to those external performance indicator figures, there is a limited supply of water, the real command area has shrunk by 28.2% from its original plan, and some of the initially installed structures are starting to fail. The overall performance is generally regarded as a good performance. As a result, for water users association to carry out its duties, the right organizational structure, plan monitoring, and capacity building must be in place. Keywords: Blue Nile, Wurko, Irrigation, CROPWAT, efficiency