The accurate determination of interaction energies and structures of hydrogen-bonded complexes has been an important issue of ab initio theory for a long time. Extensive theoretical studies have been performed to correct electronic correlation and the basis set truncation error (BSTE) that is a consequence of the incompleteness of the one-electron basis set. We have used recently developed multilevel methods to calculate the structures, harmonic frequencies and the dissociation energies of the HF and water dimers. The seven multilevel methods, namely SAC-MP2/cc-pVDZ, SAC-MP4SDQ/cc-pVDZ, MC-QCISD, MCCM-CO-MP2, MCCM-UT-MP4SDQ, MCCM-UT-CCSD, and MCG3, have been tested. The MC-QCISD, MCCM-UT-MP4SDQ, MCCM-UT-CCSD, and MCG3 method predict the structures and harmonic frequencies of HF and H2O dimers reasonably well compared with experiments and high level ab initio results. Particularly, the MCCM-UT-MP4SDQ and MCCM-UT-CCSD methods show very good agreement of both the interfragment distances and the dissociation energies with experiments using significantly less cost than the high-level ab initio calculations.