In a golf ball having a core, an intermediate layer and a cover, the core is formed primarily of a base rubber and has a diameter set in a specific range, and the intermediate layer and cover are each formed of resin materials. The core has an internal hardness such that, regarding the hardness at the core center, the hardnesses at positions located at 2 mm intervals from the core center outward up to 16 mm and the core surface hardness, the hardness differences therebetween are set within a specific range. The ball surface hardness is set so as to be higher than the surface hardness of the intermediate layer-encased sphere. This ball achieves a satisfactory distance on full shots not only with a driver, but also with a long iron or a middle iron, in addition to which it has an excellent durability to repeated impact.