We took our time to find someone with broad and international experience. Earnest fits this profile perfectly with his past and his current role.
The 53-year-old will officially begin work in the Netherlands on March 1, and has signed a contract to the end of the 2026-27 season.
Stewart is the replacement for John De Jong, who left PSV in September 2022.
PSV CEO Marcel Brands said: "We took our time to find someone with broad and international experience. Earnest fits this profile perfectly with his past and his current role. Therefore, we are delighted that he will join our Board of Directors as of 1st March."
Stewart played over 100 times for USA but actually grew up in the Netherlands and played for VVV-Venlo, Willim II and NAC Breda before joining DC United in Major League Soccer.
Following his retirement as a player, he worked as Sporting Director for VVV-Venlo, NAC and AZ in the Netherlands and then for MLS side Philadelphia Union. In 2018, he joined US Soccer as General Manager of the Men’s National Team and was elevated to the role of Sporting Director in 2019.