Punishment is considered a very old penal procedure and it is implemented widely across the globe. The modern theory in the studies of criminal penalty has changed due to the implementation of precautionary measures which plays an important part in the present criminal legislations, whether it is for the replacement of punishment or its implementation in case of loss of responsibility due to mental disease or minor age. This research discusses and explains the precautionary measures in the Omani legislation – theory and implementation through the identification of precautionary measures, its characteristics or features and conditions of implementation are discussed in the first part and in its second part, the situation of the Omani penal legislation towards the precautionary measures is discussed. Moreover, the research adobts the analysis methods by referring to the legal expression, analyzing it and finding its origin and legal content.