Dutchman De Vries was available on a Bosman transfer with his contract with the Barclays Premier League newcomers expiring on July 1. He will follow midfielder Jamie O'Hara, who signed from Tottenham in a £5million deal on Tuesday, to Molineux.
De Vries will provide competition for Wayne Hennessey after the release of Marcus Hahnemann. He said: "I'm really pleased and positive about the move. As soon as I got the call from Wolves I had a really good vibe about it and a positive feeling."
He added: "I thought this would be the fresh step I need in terms of progressing.
"That's all I look for as a player - to progress every year on and off the pitch both as a goalkeeper and as a person.
"This is a totally different challenge for me."
De Vries added: "At Swansea I have been number one for a few years now having had four great seasons and seeing the club go from League One up to the Premier League.
"We got promoted through the play-offs at Wembley which was a great experience but this is the next step for me.
"Wolves are a club with all the fundamentals in place to grow and expectations are higher than at Swansea at this moment in time.
"It was a difficult decision for me to leave Swansea and did cause a few sleepness nights. I had a great time at Swansea and a great relationship with all the guys there who I have worked with for the last four years."
Source: PA
Source: PA