The couple will tie the knot in an intimate ceremony after Jolie, who is rumoured to be expecting twins, gives birth in France.
A source told Grazia: "Brad has been talking about getting married for ages. He is totally devoted to her and their children. It is the right time for them to do this.
"It will be a strictly private affair. Brad did the big celebrity-packed wedding when he married Jennifer Aniston. This time it will be an intimate family gathering.
"Angelina has said there will be no big white dress or lots of flowers. At the moment they are looking at hosting a ceremony this summer on a yacht out in the ocean, miles from land, with just their children, Brad's close family and Angelina's brother."
The source added that Jolie is considering inviting estranged father Jon Voight but wants brother James Haven to give her away.