Born and raised in Pittsburgh, Mike Barreiro has been drawing since he could hold a crayon in his little paw. Whether drawing animals on the wall or lewd images on the frosted glass in winter, he was always drawing and always politically incorrect. Ever since finding The Fantastic Four and The Silver Surfer created by Jack "King" Kirby he wanted to draw comics. At 17, he won a contest run by Marvel Comics where he created a character called Humus Sapien, which was supposed to be part of the X-Men. That never happened, but years later the character would appear in Thunderbolts.

After graduating high school, he attended the Art Institute of Pittsburgh where he learned how to paint, but found that after a year, the school concentrated on commercial art and wasn't a good fit for him. He next attended and graduated from the Joe Kubert School of Cartoon and Graphic Art. Before graduating, he was inking for DC Vertigo on Hellblazer. He worked under a contract for DC for a couple of years, and then freelanced at Marvel, Dark Horse, Defiant, and TecknoComix. After nearly ten years of inking and the implosion at comic companies, he decided to paint more and started doing murals and private commissions around Pittsburgh painting in acrylics and oils. He subsequently started teaching at the then renamed Kubert School for almost five years. This reignited his love for comics and brought him back to comic conventions after Covid, where he plans on promoting his graphic novel The Singularity and hopes to see old and new fans alike.