Serious labor shortages in the construction industry have emerged in China in recent years. This has led to a significant need for the industry to improve the poor accommodations and inferior conditions of living quarters for migrant workers by applying both technical and management methods. In order to address the problem of improving the accommodations for rural migrant construction workers in urban China, this paper uses modular construction technology to develop an innovative integrated prefabricated (prefab) accommodation system for construction workers on site. The current status of the traditional construction workers' quarters is investigated to reveal the most urgent problems in terms of health, safety, and environmental considerations. By analyzing barriers that block innovation to improved workers' quarters, the integrated prefab accommodation system is proposed in detail, with the quarters' design and operational management mode taken into account. The developed system can provide more comfortable accommodations and living conditions for migrant on-site workers, with a lower residential density and a cleaner, safer, and higher-quality lifestyle. A case study of a real-world pilot project in China is studied to validate the economic feasibility and applicability of the innovative integrated prefab quarters system. Results indicate that migrant workers should only pay about 2-3 Yuan per day, which is 1-1.5% of their daily income, for the use of the integrated prefab quarter system. The developed system provides a novel construction management mode for practitioners in the industry and can further increase the productivity of a project due to reduced physical and mental health problems of migrant workers. It is suggested that the developed system and the business mode are promoted in regions where there are large numbers of migrant construction workers.