The potential energy surface of the tetrahydropyrane ... HCl system was explored at the MP2/6-31G(d,p) level of theory. The computed geometries for the axial and equatorial conformers agree rather well with the experimental data from microwave spectroscopy. The QCISD(T)/6-31G(d,p)//MP2/6-31G(d,p) stabilization energies for the two conformers are rather similar. Further theoretical analyses suggest that the axial conformer should be slightly more stable.