A golf club head includes a first portion forming a part of a head body of the golf club head and a second portion forming another part of the head body. The first portion is made of a first metal material and includes an abutting portion. The second portion is made of a second metal material and includes an abutting portion. At least one inclined or arcuate surface for friction welding is formed on the abutting portion of the first portion. The inclined or arcuate surface for friction welding provides the abutting portion of the first portion and the abutting portion of the second portion with improved bonding strength and increased joining area when joining the first portion and the second portion together by welding friction to form a golf club head product. A method for manufacturing a golf club head by friction welding is also disclosed.