Introduced to the club by director Dave Cormack, venture capitalist Crotty is heavily involved in the charity Grassroots Soccer in the US, which he set up with the son of former Pittodrie favourite Bobby Clark.
The Dons say his $1 million investment will go towards the cash pot for their new stadium and training ground project at Kingsford.
Over £6 million has been set aside so far and if planning permission is granted in the new year, Aberdeen chiefs are confident construction on the project’s opening phase could begin almost immediately.
Chairman Stewart Milne told the club’s official website: “It’s great to see Dave’s efforts in attracting US investment to the club come to fruition. A key part of his new role at the club was to help us source and secure investment from America and we’re staggered by this first pledge.
“Tom’s investment in the club is an endorsement of our vision and long-term strategy.”
Crotty made his fortune working in the communications and software industries, leading investments in dozens of early stage companies.
He also currently sits on the board of trustees at Notre Dame University having captained their football team during his student days. It was there that he met former Aberdeen goalkeeper and Notre Dame head coach Clark.
He helped Clark’s son Tommy set up Grassroots Soccer, with the charity using football to teach youngsters life skills.
He has now decided to plough his sizeable investment into Aberdeen after Cormack invited him to Pittodire to see the team in action.
Speaking from Boston, Crotty said: “I’m really happy to be part of what is a very exciting time for the club both on and off the pitch. My experience of soccer is that it has a profoundly positive impact across whole communities. This is why my investment is directed towards enhancing the community facilities on offer as part of the club’s modern and progressive development.
“I didn’t know much about Aberdeen but Dave and Bobby made a very compelling case for the club’s plans.
“The club has an opportunity to co-locate its community work alongside its professional football academy and stadium to create a purpose-built complex that will enhance the experience for players, act as a real magnet for young football talent and a focal point for grass-roots community initiatives.”