The research deals with the administrative and economic aspects in Mosul through the book(Qala'id Al- juman Fi Fara'id Shu'ara Hadha Al-Zaman)by Ibn Al-Sha'aar Al-Mausili.In spite of this book specialized on literature and poetry,it indicated to those aspects,whereas the functions diversified as:jurisdiction,composers bookcasing,financial functions,and ete.As to the economic aspects,Ibn Al-Sha'aar mentioned lifeways,professions,and works which`the people of Mosul were practicing to get their livelihood such as earning by poetry,weaving, scribing and ete.He also indicated to the economic state of the personality he wrote its biography.