Abstract: In this paper, we present the explicit expressions of the gauge operators for pseudoscslar fields in a gauge theory coupled vector and axial-vector fields with the aid of the method of operator algebras.The gauge operators of the pure gauge field theory under the chiral group SU(N)×SU(N) are also presented. P9oreover, the explicit expression of the Baker-Hausdorff formula is obtained for a special case and the general situation is discussed.