Walking on the toes or the ball of the foot, also known as toe walking, is fairly common in children who are just beginning to walk. Most children outgrow toe walking. Kids who continue toe walking beyond the toddler years often do so out of habit. As long as your child is growing and developing normally, toe walking on its own is unlikely to be a cause of concern.
Toe walking is sometimes the result of cerebral palsy, muscular dystrophy or another generalized disease of nerve and muscle. Children with autism also may walk on their toes or the balls of their feet, but many do not.
View source- www.mayoclinic.org