On 7 th May 1611, the construction of Esfahan Shah mosque started to be a part of the re-modeling of Safavid capital, a building that adopts a glazed bulbous double dome as a hybrid structure of brick and wooden elements. This paper aims to present building techniques, construction process and conservation works of this complex dome through historical evidence and onsite surveying. For these purposes, following a brief history of the building, the paper explores the geometry, morphology and construction sequences. It subsequently addresses the conservation during the last century from Salnameh (1934-36) up to current intervention and their consequences. The paper necessarily illustrates cracks pattern, not only to recognize its causes via their type and geometry but also to address historical performance and structural capacity. According to the objectives, the study of the Shah dome plays an important role to better understand other similar cases. This paper concludes that structural analysis and future conservation could benefit from the achievements derived from historical research, which also allow further understanding of construction techniques.