This thesis aims to study the air carrier liability in accordance with Montreal convention (1999) which has been legalized by the Sultanate of Oman in 25th June 2006 in pursuance at the royal decree No: 65/2006. Also, it will consider the provisions of the law of Oman considering the contracts of air transport with the following details: 1: explain the meaning of air carrier and how is the law of Oman is applied in this field.2 Examining the developments of air transport since Warsaw convention (1929) and its amended protocols until Montreal convention (1999), and how does it undergo the Omani inertial transport. 3: Exploring the report of responsibilities of air transport relying on the basis at this responsibility, its types and the way of application. 4, This study will explore the provisions of liability lawsuit by studying the suit parties and the court specialized in determination of such suits as well as the appointments of bringing suits and the cases in which to be refused. The elements of this study has been analyzed and handled by the researcher in order to develop the law of Oman and sever those in concerned fields. The most important results that the researcher achieves are as follow: 1.The article (200) of the commercial law of Oman has not determine the means of transport which undergo its provisions. This will result in questioning the application of provisions of the commercial law of Oman. 2: Montreal convention (1999) raised the amount of compensation in case of loss, damage or defect of the registered or non-registered log gages to a thousand (1000) until of special draw rights (SDR) in comparing with Warsaw convention (1929)