Let q and f (x) be an odd characteristic and an irreducible polynomial of degree m over Fq , respectively. Then, suppose that F (x) = x m f (x+x −1 ) is irreducible over Fq . This paper shows that the conjugate zeros of F (x) with respect to Fq form a normal basis in F q 2m if and only if those of f (x) form a normal basis in Fqm and the partial conjugates given as follows are linearly independent over Fq ,where γ is a zero of F (x) and thus a proper element in F q 2m . In addition, from the viewpoint of q-polynomial, this paper proposes an efficient method for checking whether or not the conjugate zeros of F (x) satisfy the condition.