A manufacturing method for a golf club head. The method includes the steps of: casting a cast body provided with a recession thereon; cutting the cast body to form with at least one cut opening in the recession on the golf club head; adhering a carbon-fiber plate to the recession to seal the cut opening; defining a buffer groove between the carbon-fiber plate and the cast body; and filling with an elastic material into the buffer groove; processing the cast body to an end product.