The decay process K(L)-->pi0pi-/+e+/-nu(-) is studied in the vector-meson-dominance framework in the hidden symmetry scheme. We find that vector symmetry in K(L)-->pi-pi-/+e+/-nu(-) is far from the real world. The inclusion of vector mesons generates an m(pipi) dependence of the F-2(-0) form factor, and thus improves the lowest-order prediction of the chiral Lagrangian. Also, our model predicts B(K(L)-->pi0pi-/+e+/-nu(-))=5.2x10(-5). We also give a brief discussion of Kl3 in the same model.