Design and implementation of computerized based system for the diagnosis and treatment of sexually transmitted diseases, will be designed to reduce the problems such as; bulkiness of record, inaccurate diagnosis of the type of sexually transmitted diseases (STDs) which will result in wrong prescription of drugs, repetitive or monotonous computation and misplacement or damage of patients record files. The method of data collection adopted will be interview and questionnaires. The design tools that will be applied will be data flow diagram, flow charts, and algorithms. The methodologies used were Structured System Analysis and Design Methodology (SSADM) and Object Oriented Analysis and Design Methodology (OOADM). MySQL Server might be used as Database Software and ASP.Net as scripting language for the implementation for this research. Moreover this work will be able to eradicate and ensure automatic diagnostic approach to such matters as Sexually Transmitted Diseases (STDs) and to minimize time wasted in storing and retrieving patient’s record. This research has succeeded in acquainting the workers in the hospital with the knowledge of database and use of the computer system for problem solving