In this paper, geotechnical parameters and permeability of the Bazoft dam site have been investigated. The bedrock of Bazoft dam site belongs to Asmari and Jahrum (Eocene, Oligocene, and Miocene) formations. RMR (Rock Mass Rating) and GSI (Geological Strength Index) classification systems were used to evaluate the dam site. Physical, mechanical and dynamical tests were performed on samples in a rock mechanics laboratory. Shear strength parameters and geotechnical parameters of the rock mass were determined. The results of Lugeon tests for determining of rock mass permeability were in the range of 10 to 30. Based on the RMR, the dam site is located in the good category. Finally, the relationship between Lugeon, the number of joints and RQD of the rock mass was evaluated using statistical analysis for 24 exploratory boreholes with a total length of 3400 m. The values of these parameters were determined and analyzed using equations, tables and reports in sections of 5-meters along the borehole. The results showed that the relationship between Lugeon with RQD and the joint number is an exponential equation with good correlation coefficient. The multiple linear analysis also showed high accuracy of the estimate Lugeon based on RQD and joint number.