The couple, who have six children, hired a team of builders to construct the huge facility with a series of ramps, dips and metal grinds in the backyard of their mansion in Los Feliz, Los Angeles for Shiloh's eight birthday on May 27.
A source told Celebdigs.com that the workers began transforming their beautiful garden into the skateboard park, which includes a ramp that's made to look like an abandoned pool, last month.
Asked about Shiloh's birthday, the 'Maleficent' actress previously told E! News: "We did a lot of things. She's very into skating. She's a skateboarder. We did graffiti lessons and skateboarding."
The couple also have five other children together, Maddox, 13, Pax, 10, Zahara, 9, and five-year-old twins, Knox and Vivienne.
Brad originally purchased the 5,338-square-foot property for $1.7 million in 1994, but has since bought four neighbouring homes and turned it into a lavish estate for their huge family.
The duo also own mansions in Italy, New Orleans, Malibu and New York.