To prevent a parent pin from falling down as a hole of the pin gradually becomes larger during use thereof by a method wherein an inclined insertion hole is provided at required locations in the parent pin with a needle and a needle of a child pin separately prepared is inserted into the inclined holes so as to be driven into a wall, thereby to provide a plurality of needles, which intersect one another, so that the parent pin is fixed.

An inclined insertion hole 3 is provided at required locations in a parent pin 1 with a needle 4. A child pin 2 with a needle 4 is separatly provided. And in the case that sheets or the like are pasted to a fragile wall such as gypsum wall, the parent pin 1 is perpendicularly driven in at required locations and a needle of child pin 2 is inserted into the holes 3 provided obliquely in the pin 1 to drive it into the wall, so that a plurality of intersecting needles are provided to fix the pin 1. As a result, during usage, the pine 1 is prevented from falling down even if a pin hole gradually becomes larger, and hence the pin 1 can be firmly fixed even to a fragile wall.