He was born and raised in Quincy, Massachusetts. He graduated from Emerson College.
Kelley landed his first major voice-over job when he was cast as the lead in Steven Spielberg’s Invasion America for The WB Network. Mikey Kelley has lent his voice to several animated projects including Scooby-Doo and the Cyber Chase, TMNT, The Super Hero Squad Show, King of the Hill, All Grown Up!, Batman: The Brave and the Bold, Phineas and Ferb, Ben 10, Harvey Beaks, Gravity Falls, Rocket Power, The Land Before Time, The Adventures of Puss in Boots, Wabbit, among others.
On the commercial front, he’s worked on a host of television and radio campaigns.
Mikey has also been featured in a variety of video games including Lego Jurassic World, Halo 3, Tony Hawk's Underground, Full Spectrum Warrior, Viewtiful Joe, Metal Gear Solid: Portable Ops, Final Fantasy XIII-2, Kinect Star Wars, as well as many others.