Method for lyophilisation of a sample of fecal microbiota. The present invention relates to a method for lyophilisation of a sample of fecal microbiota from a donor subject, comprising the following steps: A) mixing of a sample of fecal microbiota from a donor subject with a diluent selected from polyols, disaccharides to pentasaccharides, maltodextrins and mixtures thereof, and B) freezing the mixture obtained in A) at a temperature of less than -50°C, preferably of between -70°C and -100°C, followed by the lyophilisation thereof.