4,4,5,5,5-Pentafluoro-1-pentanol is prepared in a particularly advantageous manner from perfluoroethyl iodide by initially adding perfluoroethyl iodide in the presence of a radical initiator which does not carry any acyl groups to allyl alcohol and then hydrogenolytically dehalogenating the resulting 4,4,5,5,5-pentafluoro-2-iodo-1-pentanol in the presence of a catalyst, an acid binder and a diluent.