Various mosque designs appear in Indonesia, with various shapes, with or without domes. Until now the visualization of mosque formation that mosque has domes still accepted in general. Architectural forms are part of the visual language that is bound by the rules of geometry and proportion. Historically, the proportion of the Golden Section is a mathematical comparison applied to the design process. While in design, architects often involve a sense, whether the building design has been proportional or not. The research question, whether the sense of a proportional form can be measured mathematically? The results show that Golden Section elements exist in some parts of the mosque. The research explores the design of 3 mosques, At Tin Mosque in Taman Mini Indonesia Indah, Dian Al Mahri Mosque in Depok, and Trans Studio's Grand Mosque in Bandung, private built mosques, with geometric analysis methods and visual observations. The research benefits to explore the golden section are to control the building composition.