Abstarct: One of the theories which can describe the elastic form factors is generalized parton distributions (GPDs). The nucleon Dirac and Pauli form factors are described by sum of rules which lixnk two the GPD functions (H, E). Until now, there have been proposed several methods in GPDs for calculating form factors In this thesis, the Dirac and Pauli form factors of the proton and neutron are studied baxsed on the Generalized parton distributions by using the modified Gaussian functions in the range of -t<4.5 GeV^2 and -t<30 GeV^2 which theses form factors are related to parton distribution functions. After that other important quantities like as the transversely unpolarized and polarized densities for nucleon and the nucleon electric charge radius are computed and investigated which our results shows good agreement with other previous works.