Abstract: The disclosure relates to a method for preparing crosslinked bitumen/polymer compositions without using any crosslinking agent, wherein at least one bitumen and at least one polymeric composition including at least 80% by mass with respect to the mass of the polymeric composition, of a diblock copolymer of a monovinylaromatic hydrocarbon block and of a conjugate diene block having a molecular mass greater than or equal to 80,000 g mol?1 a content of 1-2 double bond units coming from the conjugate diene greater than or equal to 15% by mass with respect to the total mass of the conjugate diene units, are brought into contact, optionally with stirring, at a temperature between 180° C. and 220° C. for a period of 4 hours to 48 hours.