PURPOSE: To allow excessive quantity of resin to flow into a reserving hole to prevent burrs from occurring by a method wherein an excessive quantity reserving hole is provided on a runner part and a pressure controlling pin which can retrogress by resin pressure is inserted into this reserving hole.

CONSTITUTION: The excessive quantity reserving hole 7 is provided at some one of a sprue 2, a runner 3 and a gate 4 which constitute resin passages and a pressure controlling pin 8 which can retrogress by the resin pressure exceeding a given pressure is inserted into this reserving hole 7 and further, this pressure control pin 8 is projected and energized by an elastic substance 9 like rubber and a spring, etc. Excessive quantity of resin over one shot of quantity pushes and retrogresses the pressure control pin 8, is allowed to flow into the excessive quantity reserving hole 7, and therefore, the excessive quantity of resin flows into a parting surface 11 to prevent burrs from occurring. This method is applied to injection molding and transfer molding.