The effect of order in the visual perception of architectural aesthetics in parametric architecture Farzad Hamedi M.A Student of Architecture, North of Tehran branch, Islamic Azad Univesity, Department of Art and Architecture, Tehran, Iran. Farzad_hamedi@yahoo.com Mohammad Mahdi Mohammadi 1 M.A Student of Architecture, college of Art and Architecture, university of Kashan, Isfahan, Iran. Mohammadi_037@yahoo.com Abstract Order in architecture, especially in traditional Iranian architecture plays a key role. This role seems to be innate in all human beings has been institutionalized. But in parametric architecture due to the lack of appropriate theoretical principles written in Persian, need to look at order and its effects in parametric architecture is felt. In this article we will review the order in the comments of visual perception and then by referring to the order form concepts such as: symmetry, hierarchy, repetition (rhythm), unity (coordination), similarity and axis (direction) as common concepts to all theories, try to communicate the definition of order with the basic parametric architecture theories. This paper deals with documentary and library methods and by use of resources and documents, attempts to clarify the concept of order in the field of visual perception as well as parametric architectural style, to achieve the same theoretical basics to how to introduce order in parametric architecture. The result of the comparison between visual perception and parametric architecture, was concluded that order in parametric architecture, is flexible order, leading to unity and simplify the visual forms in architectural monuments. The target of order in parametric architecture can be making the understanding of the architectural structures easier. Keywords: Order, Visual perception, parametric architecture, Pattern 1-Corresponding Author