Bridges are structures including supports erected over a depression or an obstruction for carrying traffic and other moving loads. Currently, the Ethiopian government has given special attention for road construction sector and is to invest billions of dollars. Parallel to road construction, there is also a demand of construction of bridges. In bridge design, engineers strive to plan an economical structure that will safely transmit loads to the ground without collapsing or deforming excessively. Since it is difficult to predict the exact loading and circumstances that a bridge must withstand, all bridge designs include a substantial margin of safety. Design standards vary throughout the world, but all aim at ensuring that new bridges will provide many years of service and will maintain an adequate margin of safety against failure. Bridge design involves a number of design steps which involves tedious calculations due to the presence of moving loads and needs choice of parameters and decision. So due to the complexity and time consummates of the design we will be better off if we use bridge design programs to get better and accurate results in a short time. Recently, the use of box-girder reinforced concrete bridges is increasing from time to time in the design practice. However, there is lack of a readily available design software tool for analysis and design of box-girder reinforced concrete bridges in day-to day design practice. There are ready-made excel templates that are commonly used by bridge designers but they are not user friendly and require careful review of the input parameters which is time taking. This study aims to develop efficient software for the analysis and design of box-girder reinforced concrete bridges based on the ERA 2013 manual. Microsoft Visual Basic 2010, an upgraded and enhanced version of the popular Visual Basic programming language and compiler, a technology that enjoys an installed base of millions of programmers worldwide, will be used as a tool for developing the software. It is believed that the software will be a useful tool for designing superstructures of box-girder reinforced concrete bridges and will substitute the current design practices.