In this paper, we investigate the Ulam-Hyers stability of C*-ternary 3-Jordan homomorphisms for the functional equation f(x(1) + x(2), y(1) + y(2), z(1) + z(2)) = Sigma(1 <= i,j,k <= 2) f(x(i),y(j),z(k)) in C*-ternary algebras.