This study examines the historical context of quarantine practices in the Sultanate of Oman during the significant period spanning from 1888 to 1970 AD. The primary focus of this research centers on the systematic observation and documentation of key phenomena and various forms of quarantine as they existed within Oman's borders. The overarching goal of this study is to meticulously identify the prevalent epidemics and contagious diseases that afflicted Oman during this historical timeframe. Additionally, it aims to shed light on the modes of transmission of these diseases in that era. Moreover, the research endeavors to trace the evolution of quarantine practices across different decades of Oman's history, as well as to pinpoint the key quarantine facilities and procedures that were in operation during this period. To fulfill these objectives, the researcher has adopted a multifaceted methodology that combines historical analysis, descriptive research, and an analytical approach. This approach entails exhaustive investigation, critical examination of facts, and rigorous scrutiny and analysis to unearth pertinent information from both Arabic and foreign documents, modern studies, and relevant bibliography. The study adheres to the principles and standards of historical research methodology, subjecting its content to critical assessment, analysis, and documentation. The study is structured into several key sections, encompassing an introduction, three substantial chapters, and a conclusive section. The introductory part provides an overview of the research's scope and objectives. The first chapter delves into an exploration of epidemics and contagious diseases in Oman, elucidating the methods by which these diseases spread. It also establishes a clear understanding of the concept of epidemics and distinguishes between epidemics and plagues. This chapter delves into the factors contributing to the dissemination of epidemics and contagious diseases in Oman, shedding light on the significant diseases that plagued Oman during the study's time frame. The second chapter meticulously examines the various phases of quarantine development in Oman, offering insights into its historical evolution. The third chapter is devoted to an in-depth examination of the quarantine practices that were in place within Oman during the specified historical period. In culmination, this study yields several noteworthy conclusions. Most notably, it underscores that East Asia and India served as primary sources for the spread of epidemics and contagious diseases in Oman. It further emphasizes that these diseases were not confined to specific regions within the GCC countries, but rather, they pervaded across various areas. Furthermore, the governments of these states exhibited determined efforts to combat these diseases through diverse means and measures.