Ab initio and density functional theory (DFT) calculation for the hydrogen bond interaction between tetrahydrofuran (THF) and water is carried out using different basis sets. The role of basis set size, inclusion of diffuse functions, polarization function, electron correlation and hybrid functionals are also investigated. The binding energy for the hydrogen-bonded THF-water complex is found to be 13.65 kcal mol(-1) at MP2/6-311+G** level of theory. Moreover, the dipole-dipole interaction between THF and water is also investigated for different basis sets and level of theories. (C) 2004 Elsevier B.V. All rights reserved.