Abstract: In a multi-piece golf ball comprising a solid core, a surrounding layer, an intermediate layer, and a cover, at least one of the surrounding layer, the intermediate layer and the cover is formed of a heated mixture having a melt index of at least 1.0 dg/min and comprising (a) an olefin-carboxylic acid-optional carboxylate random copolymer and/or (d) a metal ion-neutralized olefin-carboxylic acid-optional carboxylate random copolymer; (b) a fatty acid or derivative; and (c) a neutralizing basic inorganic metal compound. The surrounding layer, the intermediate layer and the cover have a Shore D hardness of 10-55, 40-63 and 45-68, respectively, the hardness increasing in the order of surrounding layer, intermediate layer and cover. The ball is improved in feel, control, durability and flight performance.