Abstract
This paper treats of the compositional theory of Francesco di Giorgio's central axis plan church. He finds a perfect form in a circle as well as in a reguler square, and relates his observation with a human body. He develops his theory geometically, depending on the Vitruvius's theory. According to his theory, plans and facades can be composed with a commensurable module derived from a geometrical method. In general, a church volume is decided by a diameter of a circle, and detailed proportions are decided by a supposed column proportion derived from a human body (male, female, maiden).