Teymour's successor's period of ruling should be regarded as the time when libraries were at the zenith of their success and magnificence. Since the production of books and the establishment of libraries, before the invention of printing, were heavily dependent upon the spread of writing and calligraphy. So, whenever people and chiefs of the government paid attention to writing and calligraphy, books and libraries flourished. The unique feature which strengthened this issue was the continuation of this significance and glory throughout Teymourian period all over the Iran and especially Khorasan. Among the reasons of growth and flourishing of libraries is the use of libraries and books by researchers and writers to compile and collect their works. The majority of these works were written by the commission of the rulers and libraries practitioners. Among the most eminent writers and scholars who worked in Teymouri's rulers' libraries were Khand Amir, Sharafoddin Al Yazdi and Ghiasoddin Jamshid Kashani, to mention but a few.