Albion's chairman Jeremy Peace said on their official website: "We wish Adrian all the best in his new role at Leeds. His time with us has been short but positive for the club and the recruitment that has taken place in the youth department during the last few months means we are well positioned to move forward."
Boothroyd added that his 9-month stay at The Hawthorns had been enjoyable: "I'm really grateful for the opportunity I was given to be youth development manager at West Brom. I really enjoyed my time there and it was a fantastic learning experience.
"I wish everybody at Albion the very best and I'm sure both the youth department and the club as a whole will continue to prosper.
"My ambitions are to become part of a successful first team set up and Leeds have offered me a great opportunity that I couldn't turn down."