At the Age of Tanzimat, the Ottoman State witnessed all the reforms that targeted several systems. Taxes and Tenths were among the most important of those systems. This research aims to point out the rules and foundations of these two systems and attempts to evaluate the practical application of each of them in the Ajloun Governorate, which is one of the governorates created within the Velayet (Province) of Syria in 1281 H / 1864 AD. This research consists of an introduction, four chapters and a conclusion. The introduction points out the taxes and tenths before the Age of Tanzimat. The first chapter explains the administrative and financial system of the Ajloun Governorate, in addition to describing their features and their new developments. The Second chapter demonstrates the Tenths System following its development since the beginning of the Ottoman State to the stage of Tanzimat, then to the methods of collecting the tenths. The third chapter was allocated to taxes, pointing out the foundations on which the modern taxation system in the Ottoman State was based as well as the included tax types. The fourth chapter includes the allowances which are monetary values paid by the subjects to be exempted from the physical tasks imposed on them, such as the money allowance for exemption from the military service and the money allowance for the exemption from the road works. The conclusion includes the most important results of this research. The importance of this research is due to the significant period addressed in it, which is the Age of the Ottoman Tanzimat, which is considered the actual beginning of the modern Tax System in the Ottoman State. This Tax System is considered one of the foundations of the modern tax systems in the Arab Countries that were ruled by the Ottoman State including the Hashemite Kingdom of Jordan that Ajloun District became one of its regions in 1921 AD. In addressing the data, this research adopted the historical approach that is based on the narration, analysis, deduction and connecting the facts and events. Moreover, it used the quantum statistics methodology which is based on analyzing the digital data and concluding its significances. The research reached a group of results, the most prominent of them are: that the negative impacts which were reflected on the economic and social life of the people in Ajloun Governorate were not represented in the tax and tenths systems themselves, but they were represented in the methods of collecting both of them, in addition to the corruption connected to them. Bribery and interest relations were the most significant features of that corruption. Some of the corrupted mayors of villages, sheikhs of the regions state officers appeared as leaders of this corruption. The attempts made by the Ottoman State to reform these systems struggle with those groups who worked to thwart them.