In Kenya, the fraud menace has led to the collapse of big corporations. One of the key factors leading to fraud to thrive is lack of sufficient or weak anti-fraud control systems. Based on numerous reviewed fraud studies there existed knowledge gap to establish the influence of fraud risk management practices on the level of fraud occurrence on listed firms in Kenya and if firm sizes moderates the relationship. Thus, this study sought to establish the moderating effect of firm size on the relationship between fraud risk management and fraud occurrence in Kenyan listed companies. This was guided by four specific objectives. The first objective was to assess the effect of preventive controls on the level of fraud occurrence on listed companies in Kenya. The second objective was to establish the effect of detective controls on the level of fraud occurrence on listed companies in Kenya. The third objective was to evaluate the effect of corrective controls on the level of fraud occurrence on listed companies in Kenya. Finally, the fourth objective was to determine the moderating effect of firm size on the relationship between fraud risk management and the level of fraud occurrence on listed companies in Kenya. The study adopted a causal research design. Structured questionnaires were employed to collect data on a sample of 275 senior managers working in the Kenyan listed companies. The descriptive results established that all the preventive, detective and corrective controls were perceived to be effective in curbing fraud occurrence on listed companies in Kenya. Concerning fraud occurrence, the descriptive findings ascertained that the severity level of fraud cases were moderately low on listed companies in Kenya. The Multiple linear regression results revealed that only preventive and corrective controls had a profound negative effect on the degree of fraud occurrence on listed companies in Kenya. Conversely, detective controls had no significant effect on the degree of fraud occurrence on listed companies in Kenya. The study also observed that firm size had no profound effect on the relationship between the three assessed fraud risk management controls and the level of fraud occurrence on listed companies in Kenya. The major implication of the study is that the implementation of the most effective anti-fraud techniques requires the goodwill of the top management. If the top management pays no attention on seeing to it that the most effective anti-fraud techniques are properly and frequently employed. The fraud risk management controls would amount to nothing even if sufficient financial and human resources are devoted in procuring them. Additionally, corrective controls must be seriously looked into as an effective strategy of curbing fraud since they indeed are instrumental in curbing fraud.