ABSTRACT: Elasticity modulus and deformation modulus are used an input parameter in arch and concrete dam projects. Inaddition, these modules are used for the classification of intact rock and rock masses. Although the deformation andelasticity modulus are different from each other, they are often confused in practice. These modules are determinedby in-situ tests, laboratory tests and geophysical methods. In this study, the deformation and elasticity modulusdetermined by dilatometer tests and plate loading tests at Deriner /Artvin and Ermenek /Karaman dam sites andmodules obtained by laboratory test results were correlated. The module correlations in literature were compiledas well. Rock mass elasticity modulus (ED) of dilatometer test, rock mass deformation modulus (DD) of dilatometertest, rock mass elasticity modulus (EH) of plate loading test, rock mass deformation modulus (DH) of plate loadingtest, intact rock static elasticity modulus (ELSD) of laboratory tests, intact rock dynamic elasticity modulus (ELD)of laboratory tests are correlated with regression analysis. Empirical equations obtained by regression analysisperformed between rock modulus revealed high determination coefficient. The empirical equations proposed inthis study are developed with a number of limited number of data and every rock mass has specific properties. Theequations determined in this study should not be used for other projects or a cross check should be performed.