An acrylic rubber including: a polymer composition of: 70 to 99.9% by weight of a bonding unit derived from at least one (meth) acrylic acid ester selected from (meth) acrylic acid alkyl ester and (meth) acrylic acid alkoxyalkyl ester; 0.1 to 10% by weight of a bonding unit derived from a monomer containing a reactive group; and 0 to 20% by weight of a bonding unit derived from other monomer, wherein ash content is 0.15% by weight or less, total amount of sodium and sulfur in the ash is 60% by weight or more, a ratio of sodium to sulfur by weight ratio is in the range of 0.5 to 2.5, ratio of Z-average molecular weight to weight average molecular weight is 1.3 or more, and weight average molecular weight is in the range of 1,000,000 to 5,000,000.