Abstract: Provided is a railcar shock absorber rubber composition that can provide high cured rubber hardness and simultaneously achieve electrical insulating properties and suppression of a decrease in elastic modulus after strain loading, and includes a diene rubber as a main component, hydrous silicic acid or wet silica with a BET specific surface area of 70 to 130 m2/g, and carbon black with a DBP oil absorption of 130 cm3/100 g or less, wherein 30 to 100 parts by weight of the hydrous silicic acid or wet silica and 5 to 40 parts by weight of the carbon black are present based on 100 parts by weight of the total amount of the rubber component.