The anharmonicity of Li+-(H-2)(n) (n = 1, 2, and 3) complexes is studied using the vibrational self-consistent field (VSCF) approach. The H-H stretching frequency shifts of Li+-(H-2)(n) complexes are calculated with the coupled-cluster method including all single and double excitations with perturbative triples (CCSD(T)) level of theory with the cc-pVTZ basis set. The calculated IR active H-H stretching frequency in Li+-H-2, Li+-(H-2)(2) and Li+-(H-2)(3) is red-shifted by 121, 109, and 96-99 cm(-1), respectively, relative to that of isolated H-2. The calculated red shifts and their trends are in good agreement with the available experimental data.