Milo Murphy - He is the protagonist of Milo Murphy's Law, voiced by "Weird Al" Yankovic. He has a reputation for having extreme misfortune, but he is always optimistic and finds ways to overcome it. He carries a seemingly bottomless backpack with him that always seems to have what he needs for any given situation. It was given to him by his old babysitter, Veronica, whom was the only one able to handle Murphy's Law. Milo is the youngest of the three.
Zack Underwood - Voiced by Mekai Curtis, He is the new kid in Danville who becomes friends with Milo and Melissa and sticks by Milo even though he is a jinx. He is on this school's football team. He was once the lead singer of a boy band called The Lumberzacks. He has a fear of fish and considers them scarier when they are in bags. His mother is a doctor whom handles really bloody matters. Zack is the oldest of the three.