TiO2 membranes were successfully rendered hydrophobic (modified with perfluoroalkyl silanes) and evaluated by liquid entry pressure (LEP) measurements and membrane distillation (MD) tests. It was shown that the LEP is strongly depended on the pore size of the membranes and the feed composition. The obtained permeate fluxes were highest in vacuum MD. None of the membranes showed any sign of wetting during the experiments and salt retentions greater than 99.9 % were recorded and permeate qualities lower than 2 mu S cm(-1) were achieved in air gap MD and vacuum MD.