At the end of 17th century and during 18th century, after devastating Russian wars the Ottomans realized that they fell behind of the war technology of the Western militaries. In order to catch up with their Western rivals, they decided that they had to reform their education systems. For that they sent several students to abroad for education and started to translate Western books.  They established Western style military academies of engineering. They also invited foreign teachers in order to give education in these institutes and they consulted them while there were preparing the curriculum. For all these, during the modernization period, the reform (nizama-1 cedid) planers modelled mainly France, especially for teaching the applied disciplines. Since their main aim was to grasp the technology of the West, their interest focused on the applied part of sciences and mathematics. For that reason, they had a very keen interest on mathematical instruments. The main objective in this article is to examine mathematical instruments commonly used in the Ottoman empire. We examined that by dividing the subject in two periods: The Classical period (Medieval Islamic Echole) and the Modernization period (Western Echole). Our main focus in this article will be the Modernization period and the instruments used in the Ottoman military academies.