The 27-year-old has signed a three year deal with the Baggies and joins for an undisclosed fee, having spent six years in south Wales with the Swans.
The 27-year-old only played 234 minutes of Premier League football last season, and was a fringe player during his time in south Wales - having only made 36 appearances since his arrival at the club in 2012.
Speaking upon Barley's arrival in the West Midlands, West Brom manager Darren Moore told wba.co.uk: “I’m absolutely delighted Kyle has joined us. He’s got great presence about him and I am looking forward to working with him.”
Meanwhile, Bartley revealed that he was impressed by the ideas and ambitions that Moore has for the club, as they look to bounce back to the Premier League at the first time of asking.
“After speaking with Darren I knew this was the place I wanted to be be. He let me know his ideas for the season and the next few years, his ambitions for the club and he told me about the fan base and the facilities. I’m hoping to be involved quickly.”