This work focuses on the study of co-existence of superconductivity and ferromagnetismrnin general and in UGe2 superconductor in particular. Starting with a modelrnHamiltonian for the system and using Green functions formalism, we obtain expressionsrnfor Tc and superconductivity and magnetic order parameters and respectively.rnFor suitable value of the parameters the phase diagram is obtained which shows thernpossibility of the co-existence of superconductivity and ferromagnetism in UGe2.rnkeywords: Superconductivity (SC), Ferromagnetism (FM), Co-existence, Green functions