Louis Kahn has overcome the limits of Functionalist Architecture and reconnect the classical tradition to Modern Architecture. With a point of view that his special approach to historical precidents enabled him to contribute broaden the hiorizon of Modern Architecture, this paper trys to investigate and analyse Kahn's typological thoughts and practice in Architecture. In many ways his a priory and metaphysical thoughts on Architecture proved to be very similar to typology of 18th Century Neo-Classicism. And the geometry of Kahn's Architecture play a important role with respects to his typology. As a form-generator and 'parti' his geometry and its composition play a intemediate role to connect Form and Design and to realize the concrete structure. Therefore, the concept of his Form could be called an archetype and geometry be a kind of type in his architecture