Abstract: The tread of a tire for vehicles which are intended to bear heavy loads comprises a composition based on at least an elastomer matrix comprising a first diene elastomer and a thermoplastic styrene elastomer which represents at most 50% by weight of the elastomer matrix, a reinforcing filler which comprises from 20 to 50 phr of a silica, which silica represents at least 50% by weight of the reinforcing filler which varies within a range extending from 25 to 60 phr, a coupling agent and a crosslinking system. The first diene elastomer is chosen from the group consisting of polybutadienes, butadiene copolymers and mixtures thereof. The thermoplastic styrene elastomer comprises at least one rigid styrene segment and at least one flexible diene segment, which at least one flexible diene segment comprises at least 20% by weight of conjugated diene units, it being possible for the conjugated diene units to be all or in part hydrogenated.