Question: Would it be possible that Voldemort knew that Harry carried a piece of his soul in him before he tried to kill Harry? In knowing what Voldemort knew, we are able to tell more about the core motivation that Voldemort had in wanting to kill Harry. Yes, we know that he wanted to kill Harry in order to prove that he could not be stopped/megalomania or whatever, but was he willing to kill a part of himself in order to achieve that?

As per the question, when Voldemort killed Harry, wouldn't he be able to deduce that there are only two fragments of his soul left, in the snake and his own body?

Answer: 
**I believe not.**

In the final book, when Dumbledore explains the piece of soul embedded within Harry, these are his exact words (emphasis mine):

> 
> Part of Lord Voldemort lives inside Harry, and it is that which gives him the power of speech with snakes, and a connection with Lord Voldemort’s mind that he has never understood. And while that fragment of soul, **unmissed by Voldemort**, remains attached to and protected by Harry, Lord Voldemort cannot die.
> 
> 
> — *Deathly Hallows*, chapter 33 (*The Prince’s Tale*)
> 
> 
> 

Of course, there’s no way Dumbledore can be sure – I think it’s unlikely he just asked Voldemort – but his guesses when it comes to horcruxes and soul fragments have been remarkably accurate up to this point, so this one seems reasonable too.

This makes sense, given what else we’ve seen of Voldemort’s awareness of his other horcruxes/soul pieces. His soul was so fragmented and broken that he seemed completely disconnected from them, to the point that he didn’t realise several pieces had been destroyed. It follows that he wouldn’t notice that another part had disappeared (especially when it coincided with the loss of physical body; he had other things on his mind).

He knew that Harry had a connection with him, but I don’t think there’s any evidence that he knew this connection was as substantial as to be a piece of his soul. Otherwise he’d probably have been much more cautious of killing Harry. He *might* have worked it out after he tried to kill Harry in the Forest, given the way he was knocked prone, but of course by that point it was too late.
No, the Dark Lord didn’t know a piece of his soul was in Harry.
===============================================================

When Dumbledore explains to Harry what happened when they meet in King’s Cross, he tells Harry that the Dark Lord didn’t know he’d left part of his soul behind along with his body.

> 
> “You were the seventh Horcrux, Harry, the Horcrux he never meant to make. He had rendered his soul so unstable that it broke apart when he committed those acts of unspeakable evil, the murder of your parents, the attempted killing of a child. **But what escaped from that room was even less than he knew.** He left more than his body behind. He left part of himself latched to you, the would-be victim who had survived.”   
> *- Harry Potter and the Deathly Hallows, Chapter 35 (King’s Cross)*
> 
> 
> 

Additionally, the Dark Lord doesn’t feel when the Horcruxes are destroyed, so it’s unlikely that he’d feel that another piece of his soul was missing from the main part.

> 
> “Does Voldemort know when a Horcrux is destroyed, sir? Can he feel it?’ Harry asked, ignoring the portraits.
> 
> 
> ‘A very interesting question, Harry. I believe not. I believe that Voldemort is now so immersed in evil, and these crucial parts of himself have been detached for so long, he does not feel as we do.”   
> *- Harry Potter and the Half-Blood Prince, Chapter 23 (Horcruxes)*
> 
> 
> 

Despite that, up until the day before the Dark Lord’s death when he discovered that most of his Horcruxes were destroyed, the Dark Lord believed he would feel it if anything happened to his soul.

> 
> “But surely if the boy had destroyed any of his Horcruxes, he, Lord Voldemort, would have known, would have felt it? He, the greatest wizard of them all, he, the most powerful, he, the killer of Dumbledore and of how many other worthless, nameless men: how could Lord Voldemort not have known, if he, himself, most important and precious, had been attacked, mutilated?”   
> *- Harry Potter and the Deathly Hallows, Chapter 27 (The Final Hiding Place)*
> 
> 
> 

Because of this, it seems unlikely that the Dark Lord ever figured out that a piece of his soul was in Harry, since he’d presume he’d know where all the pieces of his soul were.