Estimating elastic modulus in hydrocarbon reservoirs has an important role in evaluating and developing oil and gas fields will help in appraisal of possible risks in drilling. Elastic modulus are measurable with dynamic and static methods. In dynamic method, dynamic parameters of rock are evaluated by measuring crossing velocity of compression and shear waves in insitu Conditions or in the laboratory and in static method static parameters of core in laboratory are measured by destruction tests like single axial compressive strength or three axis. Dynamic parameters are greater than the corresponding static values. So for continous (dynamic method) and logical (static method) measurement of rock mechanic parameter for the length of the well, creating practical relations between dynamic and static parameters is necessary. One of the ways to estimate elastic modulus is using DSI tools (set of sonic logs). DSI tool directly measures shear wave with higher accuracy, lower cost and continually.