Postharvest diseases severely impair the commercial quality and storability of citrus fruits, posing a major constraint on the sustainable development of the citrus industry. Although chemical fungicide treatment remains the predominant method for disease control, their prolonged and widespread use has raised significant concerns regarding pesticide residues, environmental contamination, and the emergence of resistant pathogen strains. Consequently, there is an urgent need to develop safe, effective, and environmentally sustainable alternatives. This paper systematically reviews the types and characteristics of pathogens responsible for major postharvest infectious diseases in citrus. It discusses recent progress on physical, chemical, biological, and integrated control methods, as well as novel antimicrobial coatings and smart packaging materials in postharvest citrus disease management, along with their potential mechanisms. Additionally, it analyzes the limitations of current control measures and explores future research directions, providing a scientific basis and practical references for the green control of postharvest citrus diseases.