Lamar, 55, has held the position of USA chief marketing officer since 2002 and was responsible for the marketing of nearly 14,000 US restaurants as well as product development and business research.
He spent 10 years in various restaurant operations positions. Half of that was spent working as vice president and general manager for the McDonald's Atlanta region, which included more than 700 restaurants in four states, and more than $1bn in annual sales.
Lamar led the strategy to unify McDonald's marketing under one system, which led to the successful "I'm lovin' it" campaign.
Golden, who is responsible for new initiatives, strategic planning, plan development and ethnic marketing, will replace Lamar on April 1. He joined McDonald's in 1989 as a regional marketing supervisor for the Indianapolis region.
Lamar said: "The health and trajectory of McDonald's business continues on a path to a bright and prosperous future. It's a good time for me and my wife to turn the page knowing the brand we love is in such a good place."
Don Thompson, president of McDonald's USA, said: "Neil Golden has a proven track record of people and marketing leadership for brand McDonald's. Knowing the essence of our business, coupled with a keen insight for what resonates and motivates people makes Neil uniquely qualified to lead national marketing for the U.S. business."