This study aims to highlight a specific period of Oman's modern history that ranges from 964 AD/ 1556 BC to 1026 AD / 1617 BC. A period in which Oman was ruled for the second time by Bani Nabhan over 61 years of prosperity. The state witnessed the presence of the Portuguese in the Arabian Gulf. The study involves some details of the state. It is divided into five main chapters with subtitles and some annexes related to the study. It also deals with the restless period from the first to second Nabhani state under the rule of Imam Muhammad Ismaiyl Al Hadhari and his son Barakat until Sultan Muhesn Sulaiman took sovereignty over Nabhanian state in 1556 BC. Methodologically speaking, it was an important period to the study, it helped Bani Nabhan to reign the state again. Hence, all political events showed that Bani Nabhan were the most qualified to lead the nation in that period. The study also deals with the foundation of the second state of Bani Nabhan, their roots and some details about their Sultans' political and social lives. In addition to their power at the beginning, then the deterioration and collapse of the state. There was also a focus on the manifestation of everyday life in this state and Oman's relationship in the period with the political powers that were close to it, for example, the relationship with the Persia, Othamani, Hurmuz, and Bani Jabr. One of the most important results of this study that the second State of the Banu Nabhan sovereign, and is characterized by its independence, despite the existence of some entities in the politics of cities in Oman. Derived Nabhan Sultans built their power from the tribes of Oman. And that they relied on the Department of State and other princes. The presence of a group of scholars and judges.