Two-body decays of Lambda_b

Two body non-leptonic decays:Lambda_b-->Lambda_c P(V) are investigated. Baryon form factors of the heavy quark effective theory are employed. Form factors for renormalization in full QCD are also considered. We find that contributions of the non-factorizable terms are negligible in b-decays. Comparison with calculations in other models shows that form factors for renormalization in full QCD should be more relevant. The asymmetry parameters are negative as in the charmed baryons cases. An experimental measure on the form factors V1 and A1 is accentuated to test the validity of HQET.