The invention relates to a rubber composition that is free of zinc or that contains less than 0.5 phr of zinc, which can be used for the manufacture of tyres, based on at least: one diene elastomer; one sulphur-based crosslinking system; one inorganic filler as reinforcing filler; one blocked mercaptosilane of general formula I below: (HO)3-nR1n—Si—Z—S—C(═O)-A in which: R1, which are identical or different, each represent a monovalent hydrocarbon-based group chosen from alkyls, which are linear or branched, cycloalkyls or aryls, having from 1 to 18 carbon atoms; A represents hydrogen or a monovalent hydrocarbon-based group chosen from alkyls, which are linear or branched, cycloalkyls or aryls, having from 1 to 18 carbon atoms; Z represents a divalent bonding group comprising from 1 to 18 carbon atoms; n is an integer equal to 0, 1 or 2.