Stanley Bolland, from Waterlooville in Hampshire, said he was the “man for the job” after the Windsor attraction advertised for the role of stand-in model maker.
In his letter, written when he was six, Stanley said: “I love Lego and have a box of it. I hide my Lego so my brother can’t get it.
“I am the man for the job because I have lots of experience.”
The company replied to Stanley: “Loving Lego is the first step to being a model maker, so it certainly sounds like you’ll be perfect for the job (once you’ve finished school of course).
“In the meantime, we’d love to offer you a one-off work experience day with our model makers.”
Stanley spent the day shadowing staff member Paula Laughton, carrying out checks and repairs, before getting a behind-the-scenes tour.
He said: “It was awesome to spend the whole day at Legoland meeting the model makers and learning all about what they do every day.
“I loved it and I can’t wait to tell all my friends about it at school.”