Warwick Davis and Tom Felton were amongst the cast who oversaw the ceremony, which took place on April 7.
The park is the second of its kind to open in the US, following the launch of the inaugural Orlando attraction in 2010 and another Wizarding World later in Japan.
The amusement features replica buildings and landmarks from the book and film series, created by J.K Rowling and adapted for the screen by Warner Brothers.
This includes Hogwarts Castle and the wizarding village of Hogsmeade.
Also on offer to thrill-seeking Potter fans are the park’s signature rides, “Harry Potter and the Forbidden Journey,” and the “Flight of the Hippogriff” coaster.
"I am delighted to see The Wizarding World of Harry Potter brought to life in a way that is so close to what I imagined when writing the books,” said series’ author Rowling. “I’m thrilled that Harry Potter fans can now experience the wonderful immersive experience created at Universal Studios Hollywood.”
Upon the opening of the attraction LA mayor, Eric Garcetti said: "In Los Angeles, tourism is surging. We’ve set records each of the last five years and we’re just getting started.
“The Wizarding World of Harry Potter at Universal Studios Hollywood is monumental in expanding our city’s global reach. It sends a message to visitors from across the world that LA is a place you and your family have to experience. I’m proud to see this game-changing world-class attraction open. Universal Studios Hollywood’s epic transformation will create new jobs, stimulate hospitality revenues and make our economy stronger."
