The sanction of "decheance" is a derogation from the general rules of civil liability, and it is one of the civil sanctions for the insurance contract, in which the insured is punished for his conduct more than for the intention of compensating the insurer for the damage suffered, and obliges the insured in the event of a breach of his obligation to announce the incident during a certain period. This study addresses the concept of "decheance" sanction; its definition and legal regulation on the one hand, and its effects and an assessment of the extent to which the insured is protected from "decheance" sanction into maritime insurance on the other hand, under the Civil Code and the Maritime Trade Act. Through this study, it was concluded that the legislator did not regulate the "decheance" sanction in the Maritime Trade Act, and merely stated the obligation of the insured to report the disaster within a certain period, and therefore, if problems arise as to the "decheance" sanction in the maritime insurance contract, then it will be referred to the general rules regulating it in the Civil Code. Notwithstanding the specificity of the maritime insurance contract with respect to other insurance contracts, which may cause legal problems, that the legislator can remedy it, if this sanction is regulated in conformity with the nature of the maritime insurance. The legislative regulation of this sanction also protects the insured, in light of the fact that the maritime insurance contract is a contract of obligation in which the insured is the weakest party to the contractual relationship. In which the researcher wished the legislator to regulate this sanction in the Maritime Trade Act in a manner consistent with the maritime insurance contract.