Rubber composition for tennis ball

A rubber composition for a tennis ball, the rubber composition including a base rubber and a high-flatness filler, wherein

• the high-flatness filler has an average particle diameter D50 of not less than 1 μm and not greater than 50 μm,
• a degree of flatness DL obtained by dividing the average particle diameter D50 by an average thickness T of the high-flatness filler is not less than 40 and not greater than 200,
• an amount of the high-flatness filler per 100 parts by weight of the base rubber is not less than 5 parts by weight and not greater than 100 parts by weight, and
• when a tensile elastic modulus, of a vulcanized rubber obtained by vulcanizing the rubber composition with sulfur, in a tensile strain range from 10% to 30% that is measured at a temperature of 23±1° C. according to JIS K6251, is denoted by E1, and a tensile elastic modulus of the vulcanized rubber in a tensile strain range from 70% to 100% that is measured at a temperature of 23±1° C. according to JIS K6251, is denoted by E2, a ratio (E2/E1) is not less than 0.60 and less than 1.00.