A majorana fermion is a fermion that is its own anti particle . In condensed matter systems majorana fermions can emerges as bogoluibov quasiparticles . As we have electron-hole symmetry in superconductors so state with zero energy in superconducting can host majorana . The importance of this state is non-Abelian statistics , that will lead to their application in quantum computers . There are several suggestion for physical systems containing superconductivity . One of these systems is semiconducting nanowire wich is placed in proxmitiy to s-wave superconductor and an external magnetic field and spin-orbit interaction are being applied to it . The external magnetic field , the superconducting gap , or the chemical potential vary along the wire and leads to zero energy state . In this thesis we try to gain zero energy bound state in a P-type semiconducting nanowire in proximity to swave superconductor , external magnetic field and rashba spin-orbit coupling . For this , we use a quasi-degenerate perturbation theory that is a very powerful method .