The reduction of distribution line losses and costs reduction is one of the most important sections in electrical power distribution system. Throughout the world, electrical power are becoming as one of the need in the growth of any country and as the area spreading of power increasing day by day the losses occurred transmission and distribution of power from generating station to consumer consumption location also increasing. Due to the distribution system line losses, the consumer cannot use the fully electrical power energy. So, now a days every one also thinking and focusing on the elimination of both kind of constant and variable losses and competition for reducing losses in transmission and distribution lines is being introduced to increase efficiency of the electric power in the industries. In the transmission and distribution of electrical power there are many different types of losses which takes place during the transmission and distribution of electrical power some of them are taken as constant and some are variable losses and the value of variable losses can be increase or decrease as per the handling or maintenance of transmission and distribution system. The main aim is to identify all the losses in the transmission and distribution system. Distribution power losses can be divided in two groups. These are technical losses and non-technical losses. To reduce these losses, can be used different types losses reduction techniques. In this journal, the distribution losses are reduced by using voltage upgrading method and changing the larger conductor size. So, the distribution losses are reduced half of the existing system and cost of lost can be saved for annual in millions kyats.