As primary sources, documents play a significant role in historical research. In this regard, as religious documents derived from Islamic jurisprudence, temporary marriage certificates have certain principles and frameworks, providing a wealth of information on the culture, society, economy, and customs of the past. The main question of the present study was what form and content did the temporary marriage certificates in Pahlavi I era have? And what effect did the new laws have on the content of such documents? The main claim was that the temporary marriage certificates in the first half of the Pahlavi I era, in terms of form and content, were influenced by religious and customary laws, the Qajar tradition of document-drafting, and the social and class status of individuals. However, in the second half of the Pahlavi I era, new marriage laws were adopted. As a result, first, the jurisprudential aspects of such certificates were decreased and their customary aspects were increased.