The 24-year-old giant central defender joins the Wood after an impressive season on the Kent coast.
His departure from Dover follows the news that top scorer Ryan Bird has joined Maidenhead.
“Obviously, it is going to be difficult this year to replicate last season, because everyone will be looking at Boreham Wood as one of last season’s Promotion Finalists,” Parry told the club’s website.
“For me though, I am just going to try to do as well as I can, as I know that the club will want to be up there challenging again.”
Manager Luke Garrard said his patience paid off as the club made their second close season signing.
“I have spoken with Manny at length, and for me, he ticks a lot of my boxes – he is powerful, athletic, very, very strong and he scores goals from defence,” Garrard said.
“He plays in a position I want him to make his own this year and he is comfortable with coming into our shape. I think that he could be a really, really big signing.
“He is coming into a settled group of players who are progressive, and he wants to be a part of that.”