Background:In longwall mining, for the purposes production and safety, the roof exposed in the working area of a longwall face must be supported and protected. For this purpose, hydraulic support units, which are called powered roof supports, are used in the production area. Before excavating the coal from underground, excavation area has to be prepared for longwall mining equipments such as powered roof supports, chain conveyor and shearer-loader. These are quite expensive equipments. In this study, importance of powered roof supports is evaluated considering it’s unit cost in total costs. Equipment costs in longwall installation are specified according to equipment type. Total longwall installation cost is calculated and in order to mention importance of roof supports, percental value of powered roof support cost in total installation cost is calculated.