New experimental results are presented for the solubility of hydrogen in the ionic liquid 1-N-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) for temperatures from 313 K to 373 K and pressures up to about 9 MPa. The extended Henry's law is applied to correlate the solubility pressures. The solubility of H-2 in [bniim][PF6] is low and increases slightly with temperature. For example, at T 313 K (373 K) and p 9 MPa, only about 0.078 mol (0.106 mol) of the gas is dissolved in I kg of the ionic liquid.