The visual perception of the viewer differs from one person to another as a result of several physiological factors, although it is affected by the formation of the surrounding environment. The research paper deals with the interrelationship between the principles of visual perception of the viewer (Symmetry - Continuity - Closure – Convergence ) and principles of architectural formation (Unit - Control - Balance - Rhythm - Axial – Scale ) under the Spatial sequences (Escalation - Syllables – Climax ) in museums of fossils and aquariums, where these buildings are subject to special design and organizational criteria by studying the formation of the elements of space through criteria affecting visual perception, which are visual characteristics such as shape , color , texture, lightness, and transparency.