This is a complex issue, but I will share a few ideas that I hope will get you started.
When you refer to Maslow, the one theory that comes to my mind is his Hierarchy of Needs, which begins with satisfying one's basic bodily requirements, moves into larger circles of community and success, and culminates in self-actualization, the notion of being one's own best self. When we think about Piaget, we think about his stages of development, which are sensimotor, preoperational, concrete, and formal, an intellectual development that proceeds stage by stage.
You will notice that Maslow's Hierarchy concerns itself with human needs, physical, psychological, and social, while Piaget's theory is about cognition. This is an fairly obvious difference that you could expand upon with little difficulty. Notice that while some intellectual development is presumed in Maslow's theory, his theory does not attend to intellectual development at all. Some socialization is presumed in Piaget's theory, but his stages do not really concern themselves with this facet all that much.
How are the two similar? Both are orderly progressions, certainly, with a theory that explains human behavior, and both are are staples of educational theory.