Abstract: A golf club head includes a head body having a front flat surface as a striking face and a hollow room formed behind the front surface and a rear cap. The rear cap is pushed in the hollow room contacting with an annular edge of the hollow room, fixedly closed on the opening of the hollow room, and welded together with the head body. Then liquid non-metal material is filled in a hollow pinched layer formed between the rear cap and the hollow room, becoming a buffer block after cooled. The buffer block has a proper softness and hardness, absorbing vibration of a ball to give stability to the golf club when the ball is hit by the golf club head.