In the book, Harry uses the Elder Wand to repair his own holly wand, then returns the Elder Wand to Dumbledore’s tomb so its power will eventually die with him.

What he does

  • He first fixes his broken original wand with the Elder Wand.
  • Then he decides not to keep it.
  • He puts it back in Dumbledore’s grave, hoping its allegiance will end when Harry dies a natural death.

Book vs. film

In the book, Harry does not break the wand; that happens in the film instead.

Why he does it

Harry sees the Elder Wand as too dangerous to keep in circulation, so he chooses the safer path: repair what he needs, then give up the extra power.

TL;DR: Harry repairs his old wand with the Elder Wand, then returns the Elder Wand to Dumbledore’s tomb.