In this research we are discussing the physicochemical characteristics of sweet diesel after desulphurization alone and also these characteristics are tested with the adding of high purity HPLC ethanol (99.9%). Those fuel properties of ethanol blended with diesel were experimentally determined to find their stability and to increase their properties and efficiency in the diesel engines. First, we made 4 blends of diesel with ethanol and the fifth sample was pure diesel. The samples were 0% ethanol and 100 % diesel, the second sample was 5% ethanol and 95 % diesel, the third sample was 10 % ethanol and 90% diesel, the fourth sample was 15 % ethanol and 85 % diesel and the fifth and last sample was 20 % ethanol and 80 % diesel. The physicochemical characteristics of the diesel ethanol blends were determined by the following experiments (cetane number, ASTM distillation, flash point, pour point, kinematic viscosity, ASTM density and calorific value). the aim of this research is to obtain an optimum blend of diesel ethanol fuel to help in improving the diesel engines and to lower the emission in the engine and the exhaust gases produced in the engines. This blend we obtained in this research was done to meet the EURO 5 standards and regulations, also to help to make an economic improvement in the industry of diesel in Egypt and in the world. The diesel ethanol blend was to be an effective fuel as we will see in the different tests and ASTM methods. Many tests and experiments done during this research project and the obtained results were similar to the EURO 5 standard emissions regulation.