A cross-linked rubber product for a fuel seal is obtained by cross-linking a nitrile rubber composition including a nitrile rubber (A) containing 25 to 80% by weight of α,β-ethylenically unsaturated nitrile monomer units (a1), 20 to 75% by weight of conjugated diene monomer units (a2), and 0 to 30% by weight of cationic monomer units and/or monomer units capable of forming a cation (a3), and having a compression set ratio of 20% or less after being compressed in an atmosphere of 100° C. for 70 hours, and an inorganic filler (B) having an aspect ratio of 30 to 2,000. The content of the inorganic filler (B) is from 1 to 200 parts by weight with respect to 100 parts by weight of the nitrile rubber (A). The cross-linked rubber product is obtained by subjecting the nitrile rubber composition to secondary vulcanization at 100 to 150° C. for 1 to 24 hours.