This research is based on developing an integrated end-to-end electronic procurement system for agro-business in Nigeria with the aim of reducing information asymmetry, making agro-business more profitable and attractive by lowering transaction costs. Qualitative findings via structured questionnaire and direct one-on-one interview were carried out among farmers, farmers associations and agro input industries. Microsoft Office Excel was used as a tool to analyze all gathered data. Pinto and Slevin procurement management model was adopted to identify the critical variable of the procurement process and an architecture was designed for the system. Mathematical model of the system was developed, since the developed system is a web based, the client-side was implemented using HTML (Hypertext Markup Language) while the server-side was implemented with Hypertext Preprocessor (PHP) and the database management system used is MySQL. The implementation was done on Intel processor core i3, 1TB Hard Disk and 8GB DDR2 RAM computer system. Functional and performance tests were carried out on the system and the test showed that the system is capable of handling multiple simultaneous users with an average response time of 0.011 to 0.015 seconds.