The digital transformer trainer is an electrical instrument design in the electric power and machine laboratory used extensively to demonstrate the operation and performance of the single phase transformer. It allows easy setup on all laboratory exercises on transformer and to check the transformer efficiency and performance. In this paper, the design and implementation of a digital transformer trainer is presented. The digital transformer trainer was constructed and it aims is to incorporate the necessary measuring instrument used to determine the behaviour of a single phase transformer in one inter-connection to become a single instrument for that specific purpose. It was constructed according to specification tested and found to give reliable results on test performed with higher efficiency.