The obtained results by hydrogeological and Tectonic survey related to fresh water resources in Al-Sin Basin, indicated that the fundamental aquifer of underground water in AL-SIN region belong to Jurassic. The alimentary basin of Al-Sin spring depend upon filtration of rainfall water and snow throw Jurassic formation from north and north–east of basin. Direction of underground water circulation is toward west and south-west where we find flow place of Al-Sin spring and submarine fresh springs near seashore. Tectonical study shows the existence of fractures and fault groups with NE-SW, ENE-WSW and NW-SE directions. Groundwater movement has the same direction of fractures and faults NE-SW to ENE-WSW and Al-Sin fault structure which allow the existence of direct relation between principal Jurassic aquifer and secondary aquifer especially Cenomanian one.