Abstract
Problem of the existence of God and His relation to the world and human being is seen as one of quite old and main problems of philosophy. Though the existence of God and His essence as a knowledge subject is related to a transcendent being over this universe, human being can find rules made by Him in physical world in which stands. The concept of God constitutes one of the most involved points of Descartes’ philosophy. In fact, for Descartes, who built his philosophy on physical bases or mechanical world, to place God as condition to his metaphysics originates from the conception that if God does not exist a being does not. In this paper, we will try to explain the relation of God and human and the world in Descartes’ philosophy.