The problems caused by sedimentation in the reservoirs of storage dams increase as time passes during the operation period of these structures. The first step in managing and depletion of these sediments is to study their characteristics. In this work, mineralogical characteristics of sediments deposited in the reservoir of Letyan dam as one of the most important sources of water supply in Tehran were studied. Consequently, after knowing the minerals in these sediments, applications for these sediments were introduced. In fact, it was suggested to collect the sediments during the rest and low water seasons of the dam to provide raw materials for the production of various building materials. After surveying, sediment was collected from a station close to the dam body and XRF test was made on it. The test results showed that quartz with about 55%, alumina with about 12% and lime with about 5% are the most minerals present in the sediment sample of Letyan dam reservoir. After comparing these results with the sediments of different dams in Iran, it showed that in most of the dams, similar to the Letyan, quartz is the most mineral content. Next, results showed that the mineral content of sediment sample is within the range of the standards for the production of bricks in Iran and Germany, however, apart from the amount of quartz, the rest of the minerals in the sediment are not within the standard range for the production of clay block, and it is necessary to add compounds to the sediment. Finally, results showed that the sediments in Latyan dam reservoir have the potential to produce light grains (Lika).