18-year-old striker Joe Nuttall has signed a two-year deal with the Dons after a successful trial spell at Pittodrie.
The forward will face stiff competition for places in the Dons side with 28-goal Adam Rooney and former Scotland international David Goodwillie standing in his way, and development league sensation Lawrence Shankland knocking of the first-team door.
But the youngster will be seen as a replacement for promising goalscorer Declan McManus who left Pittodrie in search of first-team football in England last month.
Nuttall told the official Aberdeen FC website: "I am very happy to be joining Aberdeen, as it is such an historic club with a fantastic following. I'm really looking forward to what will be an exciting project ahead.
"I would also like to thank everyone at Manchester City for the last couple of years in contributing to my development."