The dissertation aimed to state the criminal liability for using doping in sport competitions. As a result of because of the absence of special criminal legislation that addresses this issue, the dissertation set its investigation on the Omani Penal Code and the complementary laws, as well as the regulation that combat doping in sport. The dissertation is carried out in a comparative study between these Omani legal documents, and the legislations of Arabic and non Arab countries that criminalized doping, aiming to answer most questions raised in this issue, and the principles of caramelizing the doping in sport, and those who will be in charge for using it. In order to answer these questions, the dissertation into three parts. The first one is as preliminary chapter that defined doping, its types and the efforts are being made to combat using in in sport. Then, in second part, set as chapter 1that addresses the philosophical and legal principles to criminalize doping in sport, and explaining when the criminal liability is applied to a person for illegal use if doping in sport. The third part includes chapter 2 that canalized criminal liability when doping is used, player liability and the liability for those who participate the commission of doping use in sport. This chapter, also, described the punishments to those who found guilty. Finally, the dissertation ended with a conclusion summarizes the main findings, and provide some recommendation to apply the criminal liability of doping use, that hope to enhance the efforts of doping combat.