Abstract: According to the principle of localized Molecular Orbitals (LMOs)^[1], the LMOs of HF, BH,LiH, Li₂,Be₂, CO and CH₄ are obtained by using our program. Since a better unitary transformation is determined, these LMOs are more rational than those given by other papers^[8,10]. In this article, we also computed the LMOenergy s, the addition energy E'and the molecular binding energy E"^[2]. By analizing the value of E", three conclusions are obtained. First, the intercation energy between the chemical bonds can not be negnected. Second, the exchange energy between LMOs is smaller than that between canonical mocecular orbitals (CMOs), so the LMOis much nearer to the classical chemical picture. Third, the larger the electron number is, the greater the exchange energy among electrons will be.