The Tudors star, 31, is planning to exchange vows with former model Horsey in a romantic ceremony in their native England.
He tells Britain's The Sunday Telegraph, "We are marrying in Dorset. It's going to be such a beautiful wedding."
And while Horsey insists she is "looking forward to a different name", Brown admits the couple has no plans to hyphenate their family names, quipping, "We can't go double-barreled, or it will be Brown Horsey."
Brown first married actress Pollyanna Rose in December, 2005, but they divorced in 2008.