The distribution transformer plays an important role in the distribution of electric energy to the customers. The reliability of DT does not only affect availability of the electric power to the customers of utility, but also economical operation of a utility. They can operate up to 30 years; but they fail within a year, due to many reasons resulting big economic and service lose on the power supplying utilities as well as the power customers. This paper has exposed the root causes of failure of the distribution transformer in EEU Dessie district Kombolcha NO. 1 and No. 2-customer service centers by using data collected from the substation, EEU, and inspecting the status of some transformers at peak hours. From the analysis conducted it was observed that the most frequently occurring causes of failure of distribution transformers in the centers were overloading, uneven power overloading, external short circuit, and lightning. In addition to identifying the causes, the researchers have proposed some remedial solutions to reduce the problems.