Introduction: The Hajj pilgrimage in Saudi Arabia represents one of the largest annual mass gatherings worldwide, posing significant public health challenges, particularly in managing infectious diseases. Given the advancements in digital technology, this review aims to assess the effectiveness of digital health surveillance systems in controlling infectious diseases among Al-Hajj pilgrims, thereby informing future public health strategies and interventions in similar mass gathering contexts. Methods: A systematic review was conducted, focusing on interventional studies and clinical trials published up to 2022 that examined the implementation and outcomes of digital health surveillance systems at the Hajj. Databases such as PubMed, Scopus, Web of Science, and the Cochrane Library were searched using a combination of relevant keywords. Studies were included if they were interventional, focused on infectious disease surveillance among Hajj pilgrims, and provided clear outcomes related to the effectiveness of the digital intervention. The selection process involved screening titles and abstracts, followed by full-text reviews, adhering to predefined inclusion and exclusion criteria. Results: Fourteen studies were included, demonstrating a range of digital interventions, from mobile apps to wearable devices. The effectiveness of these digital tools in enhancing disease surveillance was significant, with risk ratios for improved disease detection and reporting ranging from 1.5 to 2.5. Wearable health trackers increased adherence to preventive measures by 30%. Moreover, the utilization of digital health systems was associated with a 25% reduction in the need for hospital visits among pilgrims, indicating a substantial decrease in healthcare system burden. Conclusions: Digital health surveillance systems offer a promising avenue for improving infectious disease management during mass gatherings like Hajj. The substantial improvements in disease detection rates, adherence to preventive measures, and reductions in healthcare facility visits highlight the potential of digital interventions in enhancing public health outcomes. These findings support the integration of digital health technologies into public health strategies for mass gatherings, emphasizing the need for tailored, context-specific approaches.