The MO of C5H5¯ are formed by linear combination of atomic orbitals of five carbon (2s, 2px, 2py, 2pz) and five hydrogen atom(1s). The energy levels of molecular orbitals have been quantitatively evaluated and energy level diagram have been drawn. The most stable molecular orbital has eigen value - 1.0886 e.V and highest occupied molecular orbital (HOMO) has eigen value of -0.4407. The eigen vector analysis shows that HOMO has contribution of only 2pz orbitals of carbon. The population analysis also indicates that only 2pz orbitals are present in molecular orbitals 13 that is HOMO. The contribution of electrons in the formation of molecular orbitals is described on the basis of coefficient of eigen vector.