Golf ball 2 has a spherical center 10, a mid layer 12 covering this center 10, a reinforcing layer 6 covering this mid layer 12, and a cover 8 covering this reinforcing layer 6. Base polymer of the mid layer 12 is an ionomer resin. Base polymer of the cover 8 is a thermoplastic polyurethane elastomer. The cover 8 has a thickness Tc of equal to or less than 1.2 mm, and particularly equal to or less than 0.8 mm. The difference (Ho−Hc) between the central hardness Ho of the center 10 and the hardness Hc of the cover 8 is 1 or greater and 30 or less. The cover 8 has a hardness Hc of 15 or greater and 40 or less. The product (Tc·Hc) of the thickness Tc (mm) of the cover 8 and the hardness Hc of the cover 8 is equal to or less than 25.