In a multi-piece solid golf ball comprising a solid core, a cover inner layer and a cover outer layer, the solid core undergoes a deflection of 3-7 mm under a load of 100 kg, the cover inner layer has a Shore D hardness of 25-58 and a thickness of 0.5-1.4 mm, the cover outer layer has a Shore D hardness of 30-62 and a thickness of 1.2-2.3 mm, and the ratio of the thickness of the cover outer layer to the thickness of the cover inner layer is from 1.1 to 4.6. The ball is improved in playability, feel and durability.