The research work focused on looking at an analysis of the potential risk and fraud involved in mobile money transactions in Sierra Leone with a focus on Orange and Africell mobile telecommunication companies. The implementation of mobile money service like any other financial service faces risks and challenges. This research addresses fraud as a challenge in the provision of mobile money service to customers in Sierra Leone. Mobile money usage for transactions is steadily growing across Africa with the potential to revolutionize the cash-dominant economy of this continent to be cashless. With the increased use of mobile money services and number of business use cases designed each day, it is imperative to design a holistic approach to mobile money risk, security that will reduce security exposures and prevent fraud, as some mobile money service providers have lost millions of Leones to this growing threat. This research, therefore, examines the measures that mobile network operators providing mobile money services can employ to prevent fraud.