Abstract The photoconductivity spectrum of a solution of anthracene (AN) in 2,2,4,4-tetramethylpentane (TMP) was measured as a function of pressure up to 2 kbar. The threshold energies of photoionization of the solute (AN) and of the solvent (TMP) increase with pressure. The relative quantum yield for charge carrier generation decreased with increasing pressure. The concomitant reduction of the initial separation distance of the geminate charge carrier pairs may be due to an increase of the number of inelastic collisions caused by the increased density of the liquid within the sphere of Coulomb attraction of the positive ion.